diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/banglejs/AppsManagementActivity.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/banglejs/AppsManagementActivity.java
index 9137fc6ba..dcfcd235f 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/banglejs/AppsManagementActivity.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/banglejs/AppsManagementActivity.java
@@ -16,22 +16,14 @@
     along with this program.  If not, see <https://www.gnu.org/licenses/>. */
 package nodomain.freeyourgadget.gadgetbridge.devices.banglejs;
 
-import static nodomain.freeyourgadget.gadgetbridge.activities.devicesettings.DeviceSettingsPreferenceConst.PREF_DEVICE_INTERNET_ACCESS;
-
 import android.app.Activity;
-import android.app.DownloadManager;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.net.Uri;
 import android.os.Bundle;
-import android.os.Environment;
 import android.util.Base64;
-import android.view.LayoutInflater;
-import android.view.MenuItem;
-import android.view.View;
-import android.view.ViewGroup;
 import android.webkit.DownloadListener;
 import android.webkit.JavascriptInterface;
 import android.webkit.PermissionRequest;
@@ -41,19 +33,11 @@ import android.webkit.WebResourceRequest;
 import android.webkit.WebSettings;
 import android.webkit.WebView;
 import android.webkit.WebViewClient;
-import android.widget.AdapterView;
-import android.widget.ArrayAdapter;
-import android.widget.ListView;
-import android.widget.PopupMenu;
-import android.widget.TextView;
 import android.widget.Toast;
 
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
 import androidx.localbroadcastmanager.content.LocalBroadcastManager;
 
 import org.json.JSONArray;
-import org.json.JSONObject;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -65,11 +49,7 @@ import nodomain.freeyourgadget.gadgetbridge.R;
 import nodomain.freeyourgadget.gadgetbridge.activities.AbstractGBActivity;
 import nodomain.freeyourgadget.gadgetbridge.devices.DeviceCoordinator;
 import nodomain.freeyourgadget.gadgetbridge.impl.GBDevice;
-import nodomain.freeyourgadget.gadgetbridge.model.DeviceType;
-import nodomain.freeyourgadget.gadgetbridge.service.btle.TransactionBuilder;
 import nodomain.freeyourgadget.gadgetbridge.service.devices.banglejs.BangleJSDeviceSupport;
-import nodomain.freeyourgadget.gadgetbridge.service.devices.qhybrid.QHybridSupport;
-import nodomain.freeyourgadget.gadgetbridge.util.DeviceHelper;
 import nodomain.freeyourgadget.gadgetbridge.util.GB;
 import nodomain.freeyourgadget.gadgetbridge.util.Prefs;
 import static nodomain.freeyourgadget.gadgetbridge.activities.devicesettings.DeviceSettingsPreferenceConst.PREF_BANGLEJS_WEBVIEW_URL;
@@ -332,7 +312,7 @@ public class AppsManagementActivity extends AbstractGBActivity {
                 os.write(fileSaveData);
                 os.close();
             } catch (IOException e) {
-                e.printStackTrace();
+                LOG.warn("exception in onActivityResult", e);
             } finally {
                 try {
                     os.close();
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/PBWReader.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/PBWReader.java
index d4f5cdc20..ab8279296 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/PBWReader.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/PBWReader.java
@@ -160,7 +160,7 @@ public class PBWReader {
                     } catch (JSONException e) {
                         // no JSON at all that is a problem
                         isValid = false;
-                        e.printStackTrace();
+                        LOG.warn("exception 1 in constructor", e);
                         break;
                     }
 
@@ -190,7 +190,7 @@ public class PBWReader {
                         }
                     } catch (JSONException e) {
                         isValid = false;
-                        e.printStackTrace();
+                        LOG.warn("exception 2 in constructor", e);
                         break;
                     }
                 } else if (fileName.equals(platformDir + "pebble-app.bin")) {
@@ -320,7 +320,7 @@ public class PBWReader {
             } catch (IOException e1) {
                 // ignore
             }
-            e.printStackTrace();
+            LOG.warn("exception in getInputStreamFile", e);
         }
         return null;
     }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/BluetoothPairingRequestReceiver.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/BluetoothPairingRequestReceiver.java
index 99081b86a..7c429da87 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/BluetoothPairingRequestReceiver.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/BluetoothPairingRequestReceiver.java
@@ -65,7 +65,7 @@ public class BluetoothPairingRequestReceiver extends BroadcastReceiver {
                 LOG.warn("Could not abort pairing request process");
             }
         } catch (DeviceCommunicationService.DeviceNotFoundException e) {
-            e.printStackTrace();
+            LOG.warn("exception in onReceive", e);
         }
     }
 }
\ No newline at end of file
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/PebbleReceiver.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/PebbleReceiver.java
index 8e4ca405a..ecaef3f4f 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/PebbleReceiver.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/externalevents/PebbleReceiver.java
@@ -69,7 +69,7 @@ public class PebbleReceiver extends BroadcastReceiver {
             notificationSpec.title = notificationJSON.getJSONObject(0).getString("title");
             notificationSpec.body = notificationJSON.getJSONObject(0).getString("body");
         } catch (JSONException e) {
-            e.printStackTrace();
+            LOG.warn("exception in onReceive", e);
             return;
         }
 
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/DeviceCommunicationService.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/DeviceCommunicationService.java
index f6cad8ac9..994b1f19d 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/DeviceCommunicationService.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/DeviceCommunicationService.java
@@ -768,7 +768,7 @@ public class DeviceCommunicationService extends Service implements SharedPrefere
                     try {
                         handleAction(intent, action, device1);
                     } catch (DeviceNotFoundException e) {
-                        e.printStackTrace();
+                        LOG.warn("exception in onStartCommand", e);
                     } catch (Exception e) {
                         LOG.error("An exception was raised while handling the action {} for the device {}: ", action, device1, e);
                     }
@@ -1187,7 +1187,7 @@ public class DeviceCommunicationService extends Service implements SharedPrefere
         try {
             deviceStruct = getDeviceStruct(device);
         } catch (DeviceNotFoundException e) {
-            e.printStackTrace();
+            LOG.warn("exception in getDeviceStructOrNull", e);
         }
         return deviceStruct;
     }
@@ -1221,7 +1221,7 @@ public class DeviceCommunicationService extends Service implements SharedPrefere
         try {
             device = getDeviceByAddress(deviceAddress);
         } catch (DeviceNotFoundException e) {
-            e.printStackTrace();
+            LOG.warn("exception in getDeviceByAddressOrNull", e);
         }
         return device;
     }
@@ -1571,7 +1571,7 @@ public class DeviceCommunicationService extends Service implements SharedPrefere
             try {
                 removeDeviceSupport(device);
             } catch (DeviceNotFoundException e) {
-                e.printStackTrace();
+                LOG.warn("exception in onDestroy", e);
             }
         }
         GB.removeNotification(GB.NOTIFICATION_ID, this); // need to do this because the updated notification won't be cancelled when service stops
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/casio/gb6900/CasioGB6900HandlerThread.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/casio/gb6900/CasioGB6900HandlerThread.java
index dd1c4c617..b97e46a06 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/casio/gb6900/CasioGB6900HandlerThread.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/casio/gb6900/CasioGB6900HandlerThread.java
@@ -56,7 +56,7 @@ public class CasioGB6900HandlerThread extends GBDeviceIoThread {
                     try {
                         waitObject.wait(waitTime);
                     } catch (InterruptedException e) {
-                        e.printStackTrace();
+                        LOG.warn("exception in run", e);
                     }
                 }
             }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/femometer/FemometerVinca2DeviceSupport.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/femometer/FemometerVinca2DeviceSupport.java
index 8f50da02f..4f98f7907 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/femometer/FemometerVinca2DeviceSupport.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/femometer/FemometerVinca2DeviceSupport.java
@@ -229,7 +229,7 @@ public class FemometerVinca2DeviceSupport extends AbstractBTLEDeviceSupport {
             }
             builder.queue(getQueue());
         } catch (IOException e) {
-            e.printStackTrace();
+            LOG.warn("exception in onSendConfiguration", e);
         }
     }
 
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/hplus/HPlusHandlerThread.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/hplus/HPlusHandlerThread.java
index 5ba248e0b..6afbcf615 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/hplus/HPlusHandlerThread.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/hplus/HPlusHandlerThread.java
@@ -37,7 +37,6 @@ import nodomain.freeyourgadget.gadgetbridge.GBException;
 import nodomain.freeyourgadget.gadgetbridge.database.DBHandler;
 import nodomain.freeyourgadget.gadgetbridge.database.DBHelper;
 import nodomain.freeyourgadget.gadgetbridge.devices.hplus.HPlusConstants;
-import nodomain.freeyourgadget.gadgetbridge.devices.hplus.HPlusCoordinator;
 import nodomain.freeyourgadget.gadgetbridge.devices.hplus.HPlusHealthSampleProvider;
 import nodomain.freeyourgadget.gadgetbridge.entities.DaoSession;
 import nodomain.freeyourgadget.gadgetbridge.entities.HPlusHealthActivityOverlay;
@@ -98,7 +97,7 @@ class HPlusHandlerThread extends GBDeviceIoThread {
                     try {
                         waitObject.wait(waitTime);
                     } catch (InterruptedException e) {
-                        e.printStackTrace();
+                        LOG.warn("exception in run", e);
                     }
                 }
             }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huawei/HuaweiWatchfaceManager.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huawei/HuaweiWatchfaceManager.java
index 159e948d7..c893cb553 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huawei/HuaweiWatchfaceManager.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huawei/HuaweiWatchfaceManager.java
@@ -46,7 +46,7 @@ import nodomain.freeyourgadget.gadgetbridge.service.devices.huawei.requests.Send
 
 public class HuaweiWatchfaceManager
 {
-    Logger LOG = LoggerFactory.getLogger(HuaweiCoordinator.class);
+    static Logger LOG = LoggerFactory.getLogger(HuaweiCoordinator.class);
 
     public static class Resolution {
 
@@ -142,7 +142,7 @@ public class HuaweiWatchfaceManager
                 this.font_cn = parseElement(doc,"font-cn");
 
             } catch (Exception e) {
-                e.printStackTrace();
+                LOG.warn("exception in constructor", e);
             }
         }
     }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/lenovo/watchxplus/WatchXPlusDeviceSupport.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/lenovo/watchxplus/WatchXPlusDeviceSupport.java
index 45d2dfeb6..661b0e21a 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/lenovo/watchxplus/WatchXPlusDeviceSupport.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/lenovo/watchxplus/WatchXPlusDeviceSupport.java
@@ -147,7 +147,7 @@ public class WatchXPlusDeviceSupport extends AbstractBTLEDeviceSupport {
             needsAuth = false;
             new InitOperation(auth, this, builder).perform();
         } catch (IOException e) {
-            e.printStackTrace();
+            LOG.warn("exception in initializeDevice", e);
         }
         return builder;
     }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/pebble/PebbleIoThread.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/pebble/PebbleIoThread.java
index f575d18d2..d4df5c84b 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/pebble/PebbleIoThread.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/pebble/PebbleIoThread.java
@@ -387,7 +387,7 @@ class PebbleIoThread extends GBDeviceIoThread {
                 try {
                     Thread.sleep(100);
                 } catch (InterruptedException e) {
-                    e.printStackTrace();
+                    LOG.warn("exception 1 in run", e);
                 }
             } catch (IOException e) {
                 if (e.getMessage() != null && (e.getMessage().equals("broken pipe") || e.getMessage().contains("socket closed"))) { //FIXME: this does not feel right
@@ -404,7 +404,7 @@ class PebbleIoThread extends GBDeviceIoThread {
             try {
                 mBtSocket.close();
             } catch (IOException e) {
-                e.printStackTrace();
+                LOG.warn("exception 2 in run", e);
             }
             mBtSocket = null;
         }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/watch9/Watch9DeviceSupport.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/watch9/Watch9DeviceSupport.java
index 748f717ce..edccca806 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/watch9/Watch9DeviceSupport.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/watch9/Watch9DeviceSupport.java
@@ -114,7 +114,7 @@ public class Watch9DeviceSupport extends AbstractBTLEDeviceSupport {
             needsAuth = false;
             new InitOperation(auth, this, builder).perform();
         } catch (IOException e) {
-            e.printStackTrace();
+            LOG.warn("exception in initializeDevice", e);
         }
 
         return builder;
@@ -389,7 +389,7 @@ public class Watch9DeviceSupport extends AbstractBTLEDeviceSupport {
             }
             builder.queue(getQueue());
         } catch (IOException e) {
-            e.printStackTrace();
+            LOG.warn("exception in onSendConfiguration", e);
         }
     }
 
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/withingssteelhr/WithingsSteelHRDeviceSupport.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/withingssteelhr/WithingsSteelHRDeviceSupport.java
index 7b0e2b909..dbb0ffa4f 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/withingssteelhr/WithingsSteelHRDeviceSupport.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/withingssteelhr/WithingsSteelHRDeviceSupport.java
@@ -666,7 +666,7 @@ public class WithingsSteelHRDeviceSupport extends AbstractBTLEDeviceSupport {
                 }
                 addSimpleConversationToQueue(message);
             } catch (Exception e) {
-                e.printStackTrace();
+                logger.warn("exception in setWorkoutActivityTypes", e);
             }
         }