diff --git a/app/proguard-rules.pro b/app/proguard-rules.pro
index 6c095261f..228e131ae 100644
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@@ -35,7 +35,7 @@
 -keepattributes JavascriptInterface
 
 # https://github.com/tony19/logback-android/issues/29
--dontwarn javax.mail.**, javax.naming.Context, javax.naming.InitialContext
+-dontwarn javax.mail.**
 
 # To avoid any stacktrace ambiguity
 -keepattributes SourceFile,LineNumberTable
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/AbstractDeviceCoordinator.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/AbstractDeviceCoordinator.java
index e3424f418..58954df3a 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/AbstractDeviceCoordinator.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/AbstractDeviceCoordinator.java
@@ -18,6 +18,8 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 package nodomain.freeyourgadget.gadgetbridge.devices;
 
+import static nodomain.freeyourgadget.gadgetbridge.GBApplication.getPrefs;
+
 import android.app.Activity;
 import android.bluetooth.BluetoothClass;
 import android.bluetooth.BluetoothDevice;
@@ -62,12 +64,9 @@ import nodomain.freeyourgadget.gadgetbridge.model.PaiSample;
 import nodomain.freeyourgadget.gadgetbridge.model.SleepRespiratoryRateSample;
 import nodomain.freeyourgadget.gadgetbridge.model.Spo2Sample;
 import nodomain.freeyourgadget.gadgetbridge.model.StressSample;
-import nodomain.freeyourgadget.gadgetbridge.service.DeviceSupport;
 import nodomain.freeyourgadget.gadgetbridge.service.ServiceDeviceSupport;
 import nodomain.freeyourgadget.gadgetbridge.util.Prefs;
 
-import static nodomain.freeyourgadget.gadgetbridge.GBApplication.getPrefs;
-
 public abstract class AbstractDeviceCoordinator implements DeviceCoordinator {
     private static final Logger LOG = LoggerFactory.getLogger(AbstractDeviceCoordinator.class);
 
@@ -110,13 +109,13 @@ public abstract class AbstractDeviceCoordinator implements DeviceCoordinator {
         }
         Prefs prefs = getPrefs();
 
-        String lastDevice = prefs.getPreferences().getString("last_device_address","");
+        String lastDevice = prefs.getPreferences().getString("last_device_address", "");
         if (gbDevice.getAddress().equals(lastDevice)) {
             LOG.debug("#1605 removing last device");
             prefs.getPreferences().edit().remove("last_device_address").apply();
         }
 
-        String macAddress = prefs.getPreferences().getString(MiBandConst.PREF_MIBAND_ADDRESS,"");
+        String macAddress = prefs.getPreferences().getString(MiBandConst.PREF_MIBAND_ADDRESS, "");
         if (gbDevice.getAddress().equals(macAddress)) {
             LOG.debug("#1605 removing devel miband");
             prefs.getPreferences().edit().remove(MiBandConst.PREF_MIBAND_ADDRESS).apply();
@@ -201,7 +200,13 @@ public abstract class AbstractDeviceCoordinator implements DeviceCoordinator {
     }
 
     public boolean isHealthWearable(BluetoothDevice device) {
-        BluetoothClass bluetoothClass = device.getBluetoothClass();
+        BluetoothClass bluetoothClass;
+        try {
+            bluetoothClass = device.getBluetoothClass();
+        } catch (SecurityException se) {
+            LOG.warn("missing bluetooth permission: ", se);
+            return false;
+        }
         if (bluetoothClass == null) {
             LOG.warn("unable to determine bluetooth device class of " + device);
             return false;
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/binary_sensor/coordinator/BinarySensorCoordinator.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/binary_sensor/coordinator/BinarySensorCoordinator.java
index 4aa3060d4..5ed252131 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/binary_sensor/coordinator/BinarySensorCoordinator.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/binary_sensor/coordinator/BinarySensorCoordinator.java
@@ -1,4 +1,4 @@
-package nodomain.freeyourgadget.gadgetbridge.devices.um25.Coordinator;
+package nodomain.freeyourgadget.gadgetbridge.devices.binary_sensor.coordinator;
 
 import android.app.Activity;
 import android.bluetooth.le.ScanFilter;
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/amazfitband5/AmazfitBand5Coordinator.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/amazfitband5/AmazfitBand5Coordinator.java
index 7e84b9f65..4e6a1f949 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/amazfitband5/AmazfitBand5Coordinator.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/amazfitband5/AmazfitBand5Coordinator.java
@@ -53,7 +53,7 @@ public class AmazfitBand5Coordinator extends HuamiCoordinator {
             if (name != null && name.equalsIgnoreCase(HuamiConst.AMAZFIT_BAND5_NAME)) {
                 return DeviceType.AMAZFITBAND5;
             }
-        } catch (Exception ex) {
+        } catch (SecurityException ex) {
             LOG.error("unable to check device support", ex);
         }
         return DeviceType.UNKNOWN;
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/amazfitband7/AmazfitBand7Coordinator.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/amazfitband7/AmazfitBand7Coordinator.java
index 0ec498919..164ab16a2 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/amazfitband7/AmazfitBand7Coordinator.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/amazfitband7/AmazfitBand7Coordinator.java
@@ -46,7 +46,7 @@ public class AmazfitBand7Coordinator extends Huami2021Coordinator {
             if (name != null && name.startsWith(HuamiConst.AMAZFIT_BAND7_NAME)) {
                 return DeviceType.AMAZFITBAND7;
             }
-        } catch (final Exception e) {
+        } catch (SecurityException e) {
             LOG.error("unable to check device support", e);
         }
 
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/smaq2oss/SMAQ2OSSCoordinator.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/smaq2oss/SMAQ2OSSCoordinator.java
index 000926824..652cd4da3 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/smaq2oss/SMAQ2OSSCoordinator.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/smaq2oss/SMAQ2OSSCoordinator.java
@@ -1,20 +1,18 @@
 package nodomain.freeyourgadget.gadgetbridge.devices.smaq2oss;
 
-import android.annotation.TargetApi;
 import android.app.Activity;
 import android.bluetooth.BluetoothDevice;
 import android.bluetooth.le.ScanFilter;
 import android.content.Context;
 import android.net.Uri;
-import android.os.Build;
 import android.os.ParcelUuid;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.util.Collection;
 import java.util.Collections;
 
@@ -29,7 +27,6 @@ import nodomain.freeyourgadget.gadgetbridge.impl.GBDeviceCandidate;
 import nodomain.freeyourgadget.gadgetbridge.model.ActivitySample;
 import nodomain.freeyourgadget.gadgetbridge.model.DeviceType;
 import nodomain.freeyourgadget.gadgetbridge.service.DeviceSupport;
-import nodomain.freeyourgadget.gadgetbridge.service.devices.smaq2oss.SMAQ2OSSSupport;
 
 public class SMAQ2OSSCoordinator extends AbstractBLEDeviceCoordinator {
     private static final Logger LOG = LoggerFactory.getLogger(SMAQ2OSSCoordinator.class);
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/smaq2oss/SMAQ2OSSSupport.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/smaq2oss/SMAQ2OSSSupport.java
index 0dc5eecab..e7f204b60 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/smaq2oss/SMAQ2OSSSupport.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/smaq2oss/SMAQ2OSSSupport.java
@@ -1,4 +1,4 @@
-package nodomain.freeyourgadget.gadgetbridge.service.devices.smaq2oss;
+package nodomain.freeyourgadget.gadgetbridge.devices.smaq2oss;
 
 
 import android.bluetooth.BluetoothGatt;
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/AndroidUtils.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/AndroidUtils.java
index af101a6e6..07cad80df 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/AndroidUtils.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/AndroidUtils.java
@@ -17,6 +17,7 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 package nodomain.freeyourgadget.gadgetbridge.util;
 
+import android.annotation.SuppressLint;
 import android.content.ActivityNotFoundException;
 import android.content.BroadcastReceiver;
 import android.content.ContentUris;
@@ -124,6 +125,7 @@ public class AndroidUtils {
                 dynamicColorContext = DynamicColors.wrapContextIfAvailable(context, R.style.GadgetbridgeThemeDynamicLight);
             }
             int[] attrsToResolve = {R.attr.colorOnSurface};
+            @SuppressLint("ResourceType")
             TypedArray ta = dynamicColorContext.obtainStyledAttributes(attrsToResolve);
             color = ta.getColor(0, 0);
             ta.recycle();
@@ -149,6 +151,7 @@ public class AndroidUtils {
                 dynamicColorContext = DynamicColors.wrapContextIfAvailable(context, R.style.GadgetbridgeThemeDynamicLight);
             }
             int[] attrsToResolve = {R.attr.colorSurface};
+            @SuppressLint("ResourceType")
             TypedArray ta = dynamicColorContext.obtainStyledAttributes(attrsToResolve);
             color = ta.getColor(0, 0);
             ta.recycle();
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/DeviceHelper.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/DeviceHelper.java
index 77df9c41b..f16375720 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/DeviceHelper.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/DeviceHelper.java
@@ -143,7 +143,7 @@ import nodomain.freeyourgadget.gadgetbridge.devices.sony.headphones.coordinators
 import nodomain.freeyourgadget.gadgetbridge.devices.sony.headphones.coordinators.SonyWH1000XM4Coordinator;
 import nodomain.freeyourgadget.gadgetbridge.devices.sonyswr12.SonySWR12DeviceCoordinator;
 import nodomain.freeyourgadget.gadgetbridge.devices.tlw64.TLW64Coordinator;
-import nodomain.freeyourgadget.gadgetbridge.devices.um25.Coordinator.BinarySensorCoordinator;
+import nodomain.freeyourgadget.gadgetbridge.devices.binary_sensor.coordinator.BinarySensorCoordinator;
 import nodomain.freeyourgadget.gadgetbridge.devices.um25.Coordinator.UM25Coordinator;
 import nodomain.freeyourgadget.gadgetbridge.devices.vesc.VescCoordinator;
 import nodomain.freeyourgadget.gadgetbridge.devices.vibratissimo.VibratissimoCoordinator;
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/dialogs/MaterialDialogFragment.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/dialogs/MaterialDialogFragment.java
index 1b0cee5eb..27cfaacae 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/dialogs/MaterialDialogFragment.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/util/dialogs/MaterialDialogFragment.java
@@ -18,7 +18,6 @@ package nodomain.freeyourgadget.gadgetbridge.util.dialogs;
 
 import android.app.Dialog;
 import android.os.Bundle;
-import android.view.LayoutInflater;
 import android.view.View;
 
 import androidx.annotation.NonNull;
@@ -33,7 +32,7 @@ public class MaterialDialogFragment extends DialogFragment {
     @Override
     public Dialog onCreateDialog(Bundle savedInstanceState) {
         MaterialAlertDialogBuilder builder = new MaterialAlertDialogBuilder(requireActivity());
-        theDialogView = onCreateView(LayoutInflater.from(requireContext()), null, savedInstanceState);
+        theDialogView = onCreateView(getLayoutInflater(), null, savedInstanceState);
         builder.setView(theDialogView);
 
         return builder.create();
diff --git a/app/src/main/res/layout-land/activity_notification_filter.xml b/app/src/main/res/layout-land/activity_notification_filter.xml
index 44e3e9ee2..6c6a73747 100644
--- a/app/src/main/res/layout-land/activity_notification_filter.xml
+++ b/app/src/main/res/layout-land/activity_notification_filter.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<androidx.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
@@ -87,10 +87,10 @@
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent" />
 
-    <android.support.constraint.Guideline
+    <androidx.constraintlayout.widget.Guideline
         android:id="@+id/guideline"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:orientation="vertical"
         app:layout_constraintGuide_percent="0.5" />
-</androidx.support.constraint.ConstraintLayout>
\ No newline at end of file
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_qhybrid_hr_settings.xml b/app/src/main/res/layout/activity_qhybrid_hr_settings.xml
index d399c2a8a..3292e68b1 100644
--- a/app/src/main/res/layout/activity_qhybrid_hr_settings.xml
+++ b/app/src/main/res/layout/activity_qhybrid_hr_settings.xml
@@ -34,7 +34,7 @@
 
     </LinearLayout>
 
-    <Space
+    <android.widget.Space
         android:layout_width="match_parent"
         android:layout_height="20dp" />
 
diff --git a/app/src/main/res/layout/device_itemv2.xml b/app/src/main/res/layout/device_itemv2.xml
index 50ec6552a..04839ae9f 100644
--- a/app/src/main/res/layout/device_itemv2.xml
+++ b/app/src/main/res/layout/device_itemv2.xml
@@ -372,7 +372,7 @@
                     android:padding="4dp"
                     android:scaleType="fitXY"
                     card_view:srcCompat="@drawable/ic_device_set_reminders"
-                    android:tint="@color/secondarytext" />
+                    app:tint="@color/secondarytext" />
 
                 <ImageView
                     android:id="@+id/device_action_show_activity_graphs"
diff --git a/app/src/main/res/layout/sport_activity_filter.xml b/app/src/main/res/layout/sport_activity_filter.xml
index 959e609cc..dac3b29db 100644
--- a/app/src/main/res/layout/sport_activity_filter.xml
+++ b/app/src/main/res/layout/sport_activity_filter.xml
@@ -24,7 +24,7 @@
             android:layout_height="1.5dp"
             android:background="#000" />
 
-        <Space
+        <android.widget.Space
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginBottom="1dp"
@@ -43,7 +43,7 @@
             android:layout_height="1.5dp"
             android:background="#000" />
 
-        <Space
+        <android.widget.Space
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginBottom="5dp"
@@ -77,7 +77,7 @@
             android:layout_height="1.5dp"
             android:background="#000" />
 
-        <Space
+        <android.widget.Space
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginBottom="15dp"
@@ -119,7 +119,7 @@
             android:layout_height="1.5dp"
             android:background="#000" />
 
-        <Space
+        <android.widget.Space
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginBottom="15dp"
@@ -175,7 +175,7 @@
             android:layout_height="1.5dp"
             android:background="#000" />
 
-        <Space
+        <android.widget.Space
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginBottom="15dp"
@@ -217,7 +217,7 @@
             android:layout_height="1.5dp"
             android:background="#000" />
 
-        <Space
+        <android.widget.Space
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginBottom="15dp"