diff --git a/app/build.gradle b/app/build.gradle
index 4b0a9e796e..66b3675c8d 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -27,7 +27,7 @@ def generateGitBuild = { ->
         String commitObject = stdout.toString().trim()
         stringBuilder.append(commitObject)
     } catch (ignored) {
-        return "NoGitSystemAvailable";
+        stringBuilder.append('NoGitSystemAvailable')
     }
     stringBuilder.append('-')
     stringBuilder.append((new Date()).format('yyyy.MM.dd'))
diff --git a/app/src/main/java/info/nightscout/androidaps/MainActivity.java b/app/src/main/java/info/nightscout/androidaps/MainActivity.java
index 04177386c8..aead928e52 100644
--- a/app/src/main/java/info/nightscout/androidaps/MainActivity.java
+++ b/app/src/main/java/info/nightscout/androidaps/MainActivity.java
@@ -1,5 +1,6 @@
 package info.nightscout.androidaps;
 
+import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.content.pm.PackageManager;
@@ -7,6 +8,7 @@ import android.os.Bundle;
 import android.preference.PreferenceManager;
 import android.support.v4.app.Fragment;
 import android.support.v4.view.ViewPager;
+import android.support.v7.app.AlertDialog;
 import android.support.v7.app.AppCompatActivity;
 import android.support.v7.widget.Toolbar;
 import android.view.Menu;
@@ -110,7 +112,17 @@ public class MainActivity extends AppCompatActivity {
                 startActivity(i);
                 break;
             case R.id.nav_resetdb:
-                MainApp.getDbHelper().resetDatabases();
+                new AlertDialog.Builder(this)
+                        .setTitle(R.string.nav_resetdb)
+                        .setMessage(R.string.reset_db_confirm)
+                        .setNegativeButton(android.R.string.cancel, null)
+                        .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
+                            @Override public void onClick(DialogInterface dialog, int which) {
+                                MainApp.getDbHelper().resetDatabases();
+                            }
+                        })
+                        .create()
+                        .show();
                 break;
             case R.id.nav_export:
                 ImportExportPrefs.verifyStoragePermissions(this);
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 6a72ca3921..13a9816ff1 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -8,7 +8,8 @@
     <string name="nav_refreshtreatments">Refresh treatments from NS</string>
     <string name="nav_backup">Backup</string>
     <string name="nav_test_alert">Test alarm</string>
-    <string name="nav_resetdb">Reset databases</string>
+    <string name="nav_resetdb">Reset Databases</string>
+    <string name="reset_db_confirm">Do you really want to reset the databases?</string>
     <string name="nav_exit">Exit</string>
     <string name="danar_useextended_title">Use extended boluses for >200%</string>
     <string name="danar_bt_name_title">DanaR Bluetooth device</string>