diff --git a/src/androidTest/java/de/dennisguse/opentracks/content/provider/CustomContentProviderUtilsTest.java b/src/androidTest/java/de/dennisguse/opentracks/content/provider/CustomContentProviderUtilsTest.java
index dcb7c4628..f4db02647 100644
--- a/src/androidTest/java/de/dennisguse/opentracks/content/provider/CustomContentProviderUtilsTest.java
+++ b/src/androidTest/java/de/dennisguse/opentracks/content/provider/CustomContentProviderUtilsTest.java
@@ -311,7 +311,6 @@ public class CustomContentProviderUtilsTest {
         // Bottom
         long startTime = 1000L;
         // AverageSpeed
-        double minGrade = -20.11;
         TrackStatistics statistics = new TrackStatistics();
         statistics.setStartTime_ms(startTime);
         statistics.setStopTime_ms(2500L);
diff --git a/src/main/java/de/dennisguse/opentracks/DeleteAsyncTask.java b/src/main/java/de/dennisguse/opentracks/DeleteAsyncTask.java
index d82496a36..f2fcb1ac6 100644
--- a/src/main/java/de/dennisguse/opentracks/DeleteAsyncTask.java
+++ b/src/main/java/de/dennisguse/opentracks/DeleteAsyncTask.java
@@ -26,7 +26,7 @@ import de.dennisguse.opentracks.content.provider.ContentProviderUtils;
  *
  * @author Jimmy Shih
  */
-public class DeleteAsyncTask extends AsyncTask<Void, Integer, Boolean> {
+class DeleteAsyncTask extends AsyncTask<Void, Integer, Boolean> {
 
     private final long[] trackIds;
     private final Context context;
diff --git a/src/main/java/de/dennisguse/opentracks/TrackListActivity.java b/src/main/java/de/dennisguse/opentracks/TrackListActivity.java
index 2000ec8ec..40ea5d850 100644
--- a/src/main/java/de/dennisguse/opentracks/TrackListActivity.java
+++ b/src/main/java/de/dennisguse/opentracks/TrackListActivity.java
@@ -443,7 +443,7 @@ public class TrackListActivity extends AbstractListActivity implements ConfirmDe
     /**
      * Shows start up dialogs.
      */
-    public void showStartupDialogs() {
+    private void showStartupDialogs() {
         // If stats_units_key is undefined, set it
         if (PreferencesUtils.getString(this, R.string.stats_units_key, "").equals("")) {
             String statsUnits = getString(Locale.US.equals(Locale.getDefault()) ? R.string.stats_units_imperial : R.string.stats_units_metric);
@@ -466,7 +466,6 @@ public class TrackListActivity extends AbstractListActivity implements ConfirmDe
      * @param isRecording  true if recording
      */
     private void updateMenuItems(boolean isGpsStarted, boolean isRecording) {
-        boolean hasTrack = listView != null && listView.getCount() != 0;
         if (startGpsMenuItem != null) {
             startGpsMenuItem.setVisible(!isRecording);
             if (!isRecording) {
diff --git a/src/main/java/de/dennisguse/opentracks/chart/ChartView.java b/src/main/java/de/dennisguse/opentracks/chart/ChartView.java
index 1a047cb91..9d8d4c051 100644
--- a/src/main/java/de/dennisguse/opentracks/chart/ChartView.java
+++ b/src/main/java/de/dennisguse/opentracks/chart/ChartView.java
@@ -86,7 +86,7 @@ public class ChartView extends View {
     private final ChartValueSeries speedSeries;
     private final ChartValueSeries paceSeries;
 
-    private final List<ChartPoint> chartData = new ArrayList<>();
+    private final List<ChartPoint> chartPoints = new ArrayList<>();
     private final List<Waypoint> waypoints = new ArrayList<>();
     private final ExtremityMonitor xExtremityMonitor = new ExtremityMonitor();
     private final Paint axisPaint;
@@ -396,23 +396,13 @@ public class ChartView extends View {
         return false;
     }
 
-    /**
-     * Sets show pointer.
-     *
-     * @param value true to show pointer
-     */
     public void setShowPointer(boolean value) {
         showPointer = value;
     }
 
-    /**
-     * Adds data points.
-     *
-     * @param dataPoints an array of data points to be added
-     */
     public void addChartPoints(List<ChartPoint> dataPoints) {
-        synchronized (chartData) {
-            chartData.addAll(dataPoints);
+        synchronized (chartPoints) {
+            chartPoints.addAll(dataPoints);
             for (ChartPoint dataPoint : dataPoints) {
                 xExtremityMonitor.update(dataPoint.getTimeOrDistance());
                 for (ChartValueSeries i : seriesList) {
@@ -428,8 +418,8 @@ public class ChartView extends View {
      * Clears all data.
      */
     public void reset() {
-        synchronized (chartData) {
-            chartData.clear();
+        synchronized (chartPoints) {
+            chartPoints.clear();
             xExtremityMonitor.reset();
             zoomLevel = 1;
             updateDimensions();
@@ -437,50 +427,34 @@ public class ChartView extends View {
     }
 
     /**
-     * Resets scroll. To be called on the UI thread.
+     * Resets scroll.
+     * To be called on the UI thread.
      */
     public void resetScroll() {
         scrollTo(0, 0);
     }
 
-    /**
-     * Adds a waypoint.
-     *
-     * @param waypoint the waypoint
-     */
     public void addWaypoint(Waypoint waypoint) {
         synchronized (waypoints) {
             waypoints.add(waypoint);
         }
     }
 
-    /**
-     * Clears the waypoints.
-     */
     public void clearWaypoints() {
         synchronized (waypoints) {
             waypoints.clear();
         }
     }
 
-    /**
-     * Returns true if can zoom in.
-     */
-    public boolean canZoomIn() {
+    private boolean canZoomIn() {
         return zoomLevel < MAX_ZOOM_LEVEL;
     }
 
-    /**
-     * Returns true if can zoom out.
-     */
-    public boolean canZoomOut() {
+    private boolean canZoomOut() {
         return zoomLevel > MIN_ZOOM_LEVEL;
     }
 
-    /**
-     * Zooms in one level.
-     */
-    public void zoomIn() {
+    private void zoomIn() {
         if (canZoomIn()) {
             zoomLevel++;
             updatePaths();
@@ -488,10 +462,7 @@ public class ChartView extends View {
         }
     }
 
-    /**
-     * Zooms out one level.
-     */
-    public void zoomOut() {
+    private void zoomOut() {
         if (canZoomOut()) {
             zoomLevel--;
             scroller.abortAnimation();
@@ -511,7 +482,7 @@ public class ChartView extends View {
      *
      * @param velocityX velocity of fling in pixels per second
      */
-    public void fling(int velocityX) {
+    private void fling(int velocityX) {
         int maxWidth = effectiveWidth * (zoomLevel - 1);
         scroller.fling(getScrollX(), 0, velocityX, 0, 0, maxWidth, 0, 0);
         invalidate();
@@ -522,7 +493,7 @@ public class ChartView extends View {
      *
      * @param deltaX the number of pixels to scroll
      */
-    public void scrollBy(int deltaX) {
+    private void scrollBy(int deltaX) {
         int scrollX = getScrollX() + deltaX;
         if (scrollX < 0) {
             scrollX = 0;
@@ -566,7 +537,7 @@ public class ChartView extends View {
 
     @Override
     protected void onDraw(Canvas canvas) {
-        synchronized (chartData) {
+        synchronized (chartPoints) {
             canvas.save();
 
             canvas.drawColor(Color.WHITE);
@@ -623,11 +594,7 @@ public class ChartView extends View {
      */
     private void drawWaypoints(Canvas canvas) {
         synchronized (waypoints) {
-            for (int i = 0; i < waypoints.size(); i++) {
-                final Waypoint waypoint = waypoints.get(i);
-                if (waypoint.getLocation() == null) {
-                    continue;
-                }
+            for (Waypoint waypoint : waypoints) {
                 double xValue = getWaypointXValue(waypoint);
                 if (xValue > maxX) {
                     continue;
@@ -729,9 +696,6 @@ public class ChartView extends View {
         }
     }
 
-    /**
-     * Gets the x axis label.
-     */
     private String getXAxisLabel() {
         Context context = getContext();
         if (chartByDistance) {
@@ -755,9 +719,6 @@ public class ChartView extends View {
         canvas.drawText(marker, getX(value), topBorder + effectiveHeight + spacing + rect.height(), xAxisMarkerPaint);
     }
 
-    /**
-     * Gets the x axis interval.
-     */
     private double getXAxisInterval() {
         double interval = maxX / zoomLevel / TARGET_X_AXIS_INTERVALS;
         if (interval < 1) {
@@ -772,16 +733,13 @@ public class ChartView extends View {
         return interval;
     }
 
-    /**
-     * Gets the x axis marker positions.
-     */
     private List<Double> getXAxisMarkerPositions(double interval) {
         List<Double> markers = new ArrayList<>();
         markers.add(0d);
         for (int i = 1; i * interval < maxX; i++) {
             markers.add(i * interval);
         }
-        // At least 2 markers
+
         if (markers.size() < 2) {
             markers.add(maxX);
         }
@@ -798,6 +756,7 @@ public class ChartView extends View {
         int y = topBorder;
         canvas.drawLine(x, y, x, y + effectiveHeight, axisPaint);
 
+        //TODO
         int markerXPosition = x - spacer;
         for (int i = 0; i < seriesList.size(); i++) {
             int index = seriesList.size() - 1 - i;
@@ -850,23 +809,6 @@ public class ChartView extends View {
      * @param canvas the canvas
      */
     private void drawPointer(Canvas canvas) {
-        //TODO pass chartValueSeries to 2nd if
-//        int index = -1;
-//        for (int i = 0; i < seriesList.size(); i++) {
-//            ChartValueSeries chartValueSeries = seriesList.get(i);
-//            if (chartValueSeries.isEnabled() && chartValueSeries.hasData()) {
-//                index = i;
-//                break;
-//            }
-//        }
-//        if (index != -1 && chartData.size() > 0) {
-//            int dx = getX(maxX) - pointer.getIntrinsicWidth() / 2;
-//            int dy = getY(seriesList.get(index), chartData.get(chartData.size() - 1)[index + 1])
-//                    - pointer.getIntrinsicHeight();
-//            canvas.translate(dx, dy);
-//            pointer.draw(canvas);
-//        }
-
         ChartValueSeries firstChartValueSeries = null;
         for (ChartValueSeries chartValueSeries : seriesList) {
             if (chartValueSeries.isEnabled() && chartValueSeries.hasData()) {
@@ -874,9 +816,9 @@ public class ChartView extends View {
                 break;
             }
         }
-        if (firstChartValueSeries != null && chartData.size() > 0) {
+        if (firstChartValueSeries != null && chartPoints.size() > 0) {
             int dx = getX(maxX) - pointer.getIntrinsicWidth() / 2;
-            double value = firstChartValueSeries.extractDataFromChartPoint(chartData.get(chartData.size() - 1));
+            double value = firstChartValueSeries.extractDataFromChartPoint(chartPoints.get(chartPoints.size() - 1));
             int dy = getY(firstChartValueSeries, value) - pointer.getIntrinsicHeight();
             canvas.translate(dx, dy);
             pointer.draw(canvas);
@@ -884,10 +826,11 @@ public class ChartView extends View {
     }
 
     /**
-     * Updates paths. The path needs to be updated any time after the data or the dimensions change.
+     * Updates paths.
+     * The path needs to be updated any time after the data or the dimensions change.
      */
     private void updatePaths() {
-        synchronized (chartData) {
+        synchronized (chartPoints) {
             for (ChartValueSeries chartValueSeries : seriesList) {
                 chartValueSeries.getPath().reset();
             }
@@ -896,26 +839,23 @@ public class ChartView extends View {
         }
     }
 
-    /**
-     * Draws all paths.
-     */
     private void drawPaths() {
         boolean[] hasMoved = new boolean[seriesList.size()];
 
-        for (ChartPoint dataPoint : chartData) {
-            for (int j = 0; j < seriesList.size(); j++) {
-                ChartValueSeries chartValueSeries = seriesList.get(j);
+        for (ChartPoint dataPoint : chartPoints) {
+            for (int i = 0; i < seriesList.size(); i++) {
+                ChartValueSeries chartValueSeries = seriesList.get(i);
 
-
-                double value = chartValueSeries.extractDataFromChartPoint(dataPoint);
-                if (Double.isNaN(value)) {
+                if (chartValueSeries.isChartPointValid(dataPoint)) {
                     continue;
                 }
+
+                double value = chartValueSeries.extractDataFromChartPoint(dataPoint);
                 Path path = chartValueSeries.getPath();
                 int x = getX(dataPoint.getTimeOrDistance());
                 int y = getY(chartValueSeries, value);
-                if (!hasMoved[j]) {
-                    hasMoved[j] = true;
+                if (!hasMoved[i]) {
+                    hasMoved[i] = true;
                     path.moveTo(x, y);
                 } else {
                     path.lineTo(x, y);
@@ -924,24 +864,20 @@ public class ChartView extends View {
         }
     }
 
-    /**
-     * Closes all paths.
-     */
     private void closePaths() {
-        for (int i = 0; i < seriesList.size(); i++) {
-            ChartValueSeries chartValueSeries = seriesList.get(i);
+        for (ChartValueSeries chartValueSeries : seriesList) {
             int first = getFirstPopulatedChartDataIndex(chartValueSeries);
 
             if (first != -1) {
-                int xCorner = getX(chartData.get(first).getTimeOrDistance());
+                int xCorner = getX(chartPoints.get(first).getTimeOrDistance());
                 int yCorner = topBorder + effectiveHeight;
                 Path path = chartValueSeries.getPath();
                 // Bottom right corner
-                path.lineTo(getX(chartData.get(chartData.size() - 1).getTimeOrDistance()), yCorner);
+                path.lineTo(getX(chartPoints.get(chartPoints.size() - 1).getTimeOrDistance()), yCorner);
                 // Bottom left corner
                 path.lineTo(xCorner, yCorner);
                 // Top right corner
-                double value = chartValueSeries.extractDataFromChartPoint(chartData.get(first));
+                double value = chartValueSeries.extractDataFromChartPoint(chartPoints.get(first));
                 path.lineTo(xCorner, getY(chartValueSeries, value));
             }
         }
@@ -949,11 +885,11 @@ public class ChartView extends View {
 
     /**
      * Finds the index of the first data point containing data for a series.
-     * Returns -1 if no data point contains data for the series.
+     * @return -1 if no data point contains data for the series.
      */
     private int getFirstPopulatedChartDataIndex(ChartValueSeries chartValueSeries) {
-        for (int i = 0; i < chartData.size(); i++) {
-            if (chartValueSeries.isChartPointValid(chartData.get(i))) {
+        for (int i = 0; i < chartPoints.size(); i++) {
+            if (chartValueSeries.isChartPointValid(chartPoints.get(i))) {
                 return i;
             }
         }
@@ -973,8 +909,7 @@ public class ChartView extends View {
         yAxisOffset = (int) (density * Y_AXIS_OFFSET);
 
         int markerLength = 0;
-        for (int i = 0; i < seriesList.size(); i++) {
-            ChartValueSeries chartValueSeries = seriesList.get(i);
+        for (ChartValueSeries chartValueSeries : seriesList) {
             if (chartValueSeries.isEnabled() && chartValueSeries.hasData() || allowIfEmpty(chartValueSeries)) {
                 Rect rect = getRect(chartValueSeries.getMarkerPaint(), chartValueSeries.getLargestMarker());
                 markerLength += rect.width() + spacer;
@@ -1070,7 +1005,7 @@ public class ChartView extends View {
      * Returns true if the index is allowed when the chartData is empty.
      */
     private boolean allowIfEmpty(ChartValueSeries chartValueSeries) {
-        if (!chartData.isEmpty()) {
+        if (!chartPoints.isEmpty()) {
             return false;
         }
 
diff --git a/src/main/java/de/dennisguse/opentracks/content/TrackDataHub.java b/src/main/java/de/dennisguse/opentracks/content/TrackDataHub.java
index 3954d05ab..053123039 100644
--- a/src/main/java/de/dennisguse/opentracks/content/TrackDataHub.java
+++ b/src/main/java/de/dennisguse/opentracks/content/TrackDataHub.java
@@ -222,18 +222,6 @@ public class TrackDataHub implements SharedPreferences.OnSharedPreferenceChangeL
         });
     }
 
-    /**
-     * Reloads data for a {@link TrackDataListener}.
-     */
-    public void reloadDataForListener(final TrackDataListener trackDataListener) {
-        runInHandlerThread(new Runnable() {
-            @Override
-            public void run() {
-                loadDataForListener(trackDataListener);
-            }
-        });
-    }
-
     /**
      * Returns true if the selected track is recording.
      */
diff --git a/src/main/java/de/dennisguse/opentracks/content/provider/ContentProviderUtils.java b/src/main/java/de/dennisguse/opentracks/content/provider/ContentProviderUtils.java
index f57fe905b..edd46467e 100644
--- a/src/main/java/de/dennisguse/opentracks/content/provider/ContentProviderUtils.java
+++ b/src/main/java/de/dennisguse/opentracks/content/provider/ContentProviderUtils.java
@@ -69,7 +69,7 @@ public class ContentProviderUtils {
      * Maximum number of waypoints that will be loaded at one time.
      */
     public static final int MAX_LOADED_WAYPOINTS_POINTS = 10000;
-    public static final String ID_SEPARATOR = ",";
+    private static final String ID_SEPARATOR = ",";
 
     private final IContentResolver contentResolver;
     private int defaultCursorBatchSize = 2000;
diff --git a/src/main/java/de/dennisguse/opentracks/content/provider/CustomSQLiteOpenHelper.java b/src/main/java/de/dennisguse/opentracks/content/provider/CustomSQLiteOpenHelper.java
index f4c4b41f2..f545233b9 100644
--- a/src/main/java/de/dennisguse/opentracks/content/provider/CustomSQLiteOpenHelper.java
+++ b/src/main/java/de/dennisguse/opentracks/content/provider/CustomSQLiteOpenHelper.java
@@ -15,14 +15,14 @@ import de.dennisguse.opentracks.content.data.WaypointsColumns;
  * Database helper for creating and upgrading the database.
  */
 @VisibleForTesting
-public class CustomSQLiteOpenHelper extends SQLiteOpenHelper {
+class CustomSQLiteOpenHelper extends SQLiteOpenHelper {
 
     @VisibleForTesting
-    static final int DATABASE_VERSION = 25;
+    private static final int DATABASE_VERSION = 25;
     private static final String TAG = CustomSQLiteOpenHelper.class.getSimpleName();
 
     @VisibleForTesting
-    static final String DATABASE_NAME = "database.db";
+    private static final String DATABASE_NAME = "database.db";
 
 
     public CustomSQLiteOpenHelper(Context context) {
diff --git a/src/main/java/de/dennisguse/opentracks/content/provider/ShareContentProvider.java b/src/main/java/de/dennisguse/opentracks/content/provider/ShareContentProvider.java
index edf001c06..727bccdec 100644
--- a/src/main/java/de/dennisguse/opentracks/content/provider/ShareContentProvider.java
+++ b/src/main/java/de/dennisguse/opentracks/content/provider/ShareContentProvider.java
@@ -43,7 +43,7 @@ public class ShareContentProvider extends CustomContentProvider implements ICont
 
     private static final String[] COLUMNS = {OpenableColumns.DISPLAY_NAME, OpenableColumns.SIZE};
 
-    public static final String TAG = ShareContentProvider.class.getSimpleName();
+    private static final String TAG = ShareContentProvider.class.getSimpleName();
 
     private static final int URI_GPX = 0;
     private static final int URI_KML_ONLY = 1;
@@ -90,7 +90,7 @@ public class ShareContentProvider extends CustomContentProvider implements ICont
         return new Pair<>(uri, mime);
     }
 
-    protected static long[] parseURI(Uri uri) {
+    static long[] parseURI(Uri uri) {
         List<String> uriPaths = uri.getPathSegments();
         if (uriPaths == null || uriPaths.size() < 2) {
             Log.d(TAG, "URI does not contain any trackIds.");
@@ -151,7 +151,7 @@ public class ShareContentProvider extends CustomContentProvider implements ICont
     }
 
     @Nullable
-    public static String getTypeMime(@NonNull Uri uri) {
+    private static String getTypeMime(@NonNull Uri uri) {
         return getTrackFileFormat(uri).getMimeType();
     }
 
diff --git a/src/main/java/de/dennisguse/opentracks/fragments/ChartFragment.java b/src/main/java/de/dennisguse/opentracks/fragments/ChartFragment.java
index 2ff2dca17..c5a13f0fe 100644
--- a/src/main/java/de/dennisguse/opentracks/fragments/ChartFragment.java
+++ b/src/main/java/de/dennisguse/opentracks/fragments/ChartFragment.java
@@ -298,16 +298,6 @@ public class ChartFragment extends Fragment implements TrackDataListener {
         return trackDataHub != null && trackDataHub.isSelectedTrackRecording();
     }
 
-    /**
-     * Reloads the trackDataHub.
-     * Needs to be synchronized because trackDataHub can be accessed by multiple threads.
-     */
-    private synchronized void reloadTrackDataHub() {
-        if (trackDataHub != null) {
-            trackDataHub.reloadDataForListener(this);
-        }
-    }
-
     /**
      * Runs a runnable on the UI thread if possible.
      *
diff --git a/src/main/java/de/dennisguse/opentracks/fragments/ChooseActivityTypeImageAdapter.java b/src/main/java/de/dennisguse/opentracks/fragments/ChooseActivityTypeImageAdapter.java
index c6fcb7677..6470fce0e 100644
--- a/src/main/java/de/dennisguse/opentracks/fragments/ChooseActivityTypeImageAdapter.java
+++ b/src/main/java/de/dennisguse/opentracks/fragments/ChooseActivityTypeImageAdapter.java
@@ -32,7 +32,7 @@ import de.dennisguse.opentracks.util.ResourceUtils;
  *
  * @author apoorvn
  */
-public class ChooseActivityTypeImageAdapter extends BaseAdapter {
+class ChooseActivityTypeImageAdapter extends BaseAdapter {
 
     private final List<Integer> imageIds;
     private int selected = -1;
diff --git a/src/main/java/de/dennisguse/opentracks/io/file/exporter/ExportAsyncTask.java b/src/main/java/de/dennisguse/opentracks/io/file/exporter/ExportAsyncTask.java
index 7c64f62fa..761ea4c35 100644
--- a/src/main/java/de/dennisguse/opentracks/io/file/exporter/ExportAsyncTask.java
+++ b/src/main/java/de/dennisguse/opentracks/io/file/exporter/ExportAsyncTask.java
@@ -40,7 +40,7 @@ import de.dennisguse.opentracks.util.SystemUtils;
  * @author Jimmy Shih
  */
 //TODO Make independent from ExportActivity?
-public class ExportAsyncTask extends AsyncTask<Void, Integer, Boolean> {
+class ExportAsyncTask extends AsyncTask<Void, Integer, Boolean> {
 
     private static final String TAG = ExportAsyncTask.class.getSimpleName();
     private final TrackFileFormat trackFileFormat;
@@ -70,18 +70,6 @@ public class ExportAsyncTask extends AsyncTask<Void, Integer, Boolean> {
         contentProviderUtils = new ContentProviderUtils(context);
     }
 
-    /**
-     * Sets the current activity associated with this AsyncTask.
-     *
-     * @param exportActivity the current activity, can be null
-     */
-    public void setActivity(ExportActivity exportActivity) {
-        this.exportActivity = exportActivity;
-        if (completed && exportActivity != null) {
-            exportActivity.onAsyncTaskCompleted(processedTrackCount, totalTrackCount);
-        }
-    }
-
     @Override
     protected void onPreExecute() {
         if (exportActivity != null) {
diff --git a/src/main/java/de/dennisguse/opentracks/io/file/importer/ImportAsyncTask.java b/src/main/java/de/dennisguse/opentracks/io/file/importer/ImportAsyncTask.java
index 0fa86edae..5c24c0ad2 100644
--- a/src/main/java/de/dennisguse/opentracks/io/file/importer/ImportAsyncTask.java
+++ b/src/main/java/de/dennisguse/opentracks/io/file/importer/ImportAsyncTask.java
@@ -41,7 +41,7 @@ import de.dennisguse.opentracks.util.SystemUtils;
  *
  * @author Jimmy Shih
  */
-public class ImportAsyncTask extends AsyncTask<Void, Integer, Boolean> {
+class ImportAsyncTask extends AsyncTask<Void, Integer, Boolean> {
 
     private static final String TAG = ImportAsyncTask.class.getSimpleName();
     private final TrackFileFormat trackFileFormat;
@@ -81,18 +81,6 @@ public class ImportAsyncTask extends AsyncTask<Void, Integer, Boolean> {
         trackId = -1L;
     }
 
-    /**
-     * Sets the current {@link ImportActivity} associated with this AyncTask.
-     *
-     * @param importActivity the current {@link ImportActivity}, can be null
-     */
-    public void setActivity(ImportActivity importActivity) {
-        this.importActivity = importActivity;
-        if (completed && importActivity != null) {
-            importActivity.onAsyncTaskCompleted(importTrackCount, totalTrackCount);
-        }
-    }
-
     @Override
     protected void onPreExecute() {
         if (importActivity != null) {
diff --git a/src/main/java/de/dennisguse/opentracks/io/file/importer/TrackImporter.java b/src/main/java/de/dennisguse/opentracks/io/file/importer/TrackImporter.java
index 100ff0928..0b75dcd5c 100644
--- a/src/main/java/de/dennisguse/opentracks/io/file/importer/TrackImporter.java
+++ b/src/main/java/de/dennisguse/opentracks/io/file/importer/TrackImporter.java
@@ -22,7 +22,7 @@ import java.io.InputStream;
  *
  * @author Jimmy Shih
  */
-public interface TrackImporter {
+interface TrackImporter {
 
     /**
      * Import a file.
diff --git a/src/main/java/de/dennisguse/opentracks/services/LocationListenerPolicy.java b/src/main/java/de/dennisguse/opentracks/services/LocationListenerPolicy.java
index 0158dc79d..e48975e25 100644
--- a/src/main/java/de/dennisguse/opentracks/services/LocationListenerPolicy.java
+++ b/src/main/java/de/dennisguse/opentracks/services/LocationListenerPolicy.java
@@ -21,7 +21,7 @@ package de.dennisguse.opentracks.services;
  *
  * @author Sandor Dornbush
  */
-public interface LocationListenerPolicy {
+interface LocationListenerPolicy {
 
     /**
      * Returns the polling interval this policy would like at this moment.
diff --git a/src/main/java/de/dennisguse/opentracks/services/TrackRecordingServiceConnection.java b/src/main/java/de/dennisguse/opentracks/services/TrackRecordingServiceConnection.java
index d729421e5..c6f394d55 100644
--- a/src/main/java/de/dennisguse/opentracks/services/TrackRecordingServiceConnection.java
+++ b/src/main/java/de/dennisguse/opentracks/services/TrackRecordingServiceConnection.java
@@ -70,7 +70,7 @@ public class TrackRecordingServiceConnection implements ServiceConnection, Death
     /**
      * Binds the service if it is started.
      */
-    public void bindIfStarted(Context context) {
+    private void bindIfStarted(Context context) {
         bindService(context, false);
     }
 
diff --git a/src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskExecutor.java b/src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskExecutor.java
index f3348fc44..b94b7693f 100644
--- a/src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskExecutor.java
+++ b/src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskExecutor.java
@@ -30,7 +30,6 @@ import de.dennisguse.opentracks.util.UnitConversions;
 public class PeriodicTaskExecutor {
 
     private static final String TAG = PeriodicTaskExecutor.class.getSimpleName();
-    private static final long MINUTE_TO_MILLISECONDS = 60000L;
 
     private final TrackRecordingService trackRecordingService;
     private final PeriodicTaskFactory periodicTaskFactory;
@@ -93,7 +92,7 @@ public class PeriodicTaskExecutor {
             if (timerTaskExecutor == null) {
                 timerTaskExecutor = new TimerTaskExecutor(periodicTask, trackRecordingService);
             }
-            timerTaskExecutor.scheduleTask(taskFrequency * MINUTE_TO_MILLISECONDS);
+            timerTaskExecutor.scheduleTask(taskFrequency * UnitConversions.ONE_MINUTE_MS);
         } else {
             // For distance periodic task
             calculateNextTaskDistance();
diff --git a/src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskFactory.java b/src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskFactory.java
index e75581a62..ad30beb31 100644
--- a/src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskFactory.java
+++ b/src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskFactory.java
@@ -23,7 +23,7 @@ import android.content.Context;
  *
  * @author Sandor Dornbush
  */
-public interface PeriodicTaskFactory {
+interface PeriodicTaskFactory {
 
     /**
      * Creates a {@link PeriodicTask}.
diff --git a/src/main/java/de/dennisguse/opentracks/settings/SettingsActivity.java b/src/main/java/de/dennisguse/opentracks/settings/SettingsActivity.java
index e904e5f1c..abbd92b9c 100644
--- a/src/main/java/de/dennisguse/opentracks/settings/SettingsActivity.java
+++ b/src/main/java/de/dennisguse/opentracks/settings/SettingsActivity.java
@@ -48,7 +48,7 @@ public class SettingsActivity extends AppCompatActivity implements ChooseActivit
         getSupportFragmentManager().beginTransaction().replace(R.id.settings_fragment, prefsFragment).commit();
     }
 
-    public static class PrefsFragment extends PreferenceFragmentCompat {
+    private static class PrefsFragment extends PreferenceFragmentCompat {
 
         private final SharedPreferences.OnSharedPreferenceChangeListener sharedPreferenceChangeListener = new SharedPreferences.OnSharedPreferenceChangeListener() {
             @Override
diff --git a/src/main/java/de/dennisguse/opentracks/stats/DoubleBuffer.java b/src/main/java/de/dennisguse/opentracks/stats/DoubleBuffer.java
index c813b80b3..0ec4360c9 100644
--- a/src/main/java/de/dennisguse/opentracks/stats/DoubleBuffer.java
+++ b/src/main/java/de/dennisguse/opentracks/stats/DoubleBuffer.java
@@ -25,7 +25,7 @@ import androidx.annotation.NonNull;
  *
  * @author Sandor Dornbush
  */
-public class DoubleBuffer {
+class DoubleBuffer {
 
     // The sliding buffer of doubles.
     private final double[] buffer;
diff --git a/src/main/java/de/dennisguse/opentracks/util/AnnouncementUtils.java b/src/main/java/de/dennisguse/opentracks/util/AnnouncementUtils.java
index 553d30521..34f7cbe2e 100644
--- a/src/main/java/de/dennisguse/opentracks/util/AnnouncementUtils.java
+++ b/src/main/java/de/dennisguse/opentracks/util/AnnouncementUtils.java
@@ -41,7 +41,7 @@ public class AnnouncementUtils {
         return context.getString(R.string.voice_template, totalDistance, getAnnounceTime(context, trackStatistics.getMovingTime()), rate);
     }
 
-    public static String getAnnounceTime(Context context, long time) {
+    private static String getAnnounceTime(Context context, long time) {
         int[] parts = StringUtils.getTimeParts(time);
         String seconds = context.getResources()
                 .getQuantityString(R.plurals.voiceSeconds, parts[0], parts[0]);
@@ -71,7 +71,7 @@ public class AnnouncementUtils {
      *
      * @param d the double value
      */
-    public static int getQuantityCount(double d) {
+    private static int getQuantityCount(double d) {
         if (d == 0) {
             return 0;
         } else if (d == 1) {
diff --git a/src/main/java/de/dennisguse/opentracks/util/PreferencesUtils.java b/src/main/java/de/dennisguse/opentracks/util/PreferencesUtils.java
index 3ac46856a..eb3d1c7e0 100644
--- a/src/main/java/de/dennisguse/opentracks/util/PreferencesUtils.java
+++ b/src/main/java/de/dennisguse/opentracks/util/PreferencesUtils.java
@@ -93,7 +93,7 @@ public class PreferencesUtils {
      * @param keyId        the key id
      * @param defaultValue the default value
      */
-    public static boolean getBoolean(Context context, int keyId, boolean defaultValue) {
+    private static boolean getBoolean(Context context, int keyId, boolean defaultValue) {
         SharedPreferences sharedPreferences = getSharedPreferences(context);
         return sharedPreferences.getBoolean(getKey(context, keyId), defaultValue);
     }
@@ -119,7 +119,7 @@ public class PreferencesUtils {
      * @param keyId        the key id
      * @param defaultValue the default value
      */
-    public static int getInt(Context context, int keyId, int defaultValue) {
+    private static int getInt(Context context, int keyId, int defaultValue) {
         SharedPreferences sharedPreferences = getSharedPreferences(context);
 
         try {
@@ -215,7 +215,7 @@ public class PreferencesUtils {
         setBoolean(context, R.string.recording_track_paused_key, RECORDING_TRACK_PAUSED);
     }
 
-    public static String getBluetoothHeartRateSensorAddressNone(Context context) {
+    private static String getBluetoothHeartRateSensorAddressNone(Context context) {
         return context.getString(R.string.sensor_type_value_none);
     }