diff --git a/app/build.gradle b/app/build.gradle
index 8f37a376..6e94e78f 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -70,6 +70,5 @@ dependencies {
 // Third-party
     implementation 'cat.ereza:customactivityoncrash:2.3.0'
     implementation 'org.nanohttpd:nanohttpd:2.3.1'
-    //implementation 'com.maxmind.db:maxmind-db:2.0.0'
     implementation 'com.github.KaKaVip:Android-Flag-Kit:v0.1'
 }
\ No newline at end of file
diff --git a/app/src/main/java/com/emanuelef/remote_capture/Utils.java b/app/src/main/java/com/emanuelef/remote_capture/Utils.java
index 7fbe5a61..7b65e1f9 100644
--- a/app/src/main/java/com/emanuelef/remote_capture/Utils.java
+++ b/app/src/main/java/com/emanuelef/remote_capture/Utils.java
@@ -276,6 +276,10 @@ public class Utils {
     }
 
     // https://gist.github.com/mathieugerard/0de2b6f5852b6b0b37ed106cab41eba1
+    // API level 31 requires building a NetworkRequest, which in turn requires an asynchronous callback.
+    // Using the deprecated API instead to keep things simple.
+    // https://developer.android.com/reference/android/net/wifi/WifiManager#getConnectionInfo()
+    @SuppressWarnings("deprecation")
     public static String getLocalWifiIpAddress(Context context) {
         WifiManager wifiManager = (WifiManager) context.getApplicationContext().getSystemService(Context.WIFI_SERVICE);
         WifiInfo connInfo = wifiManager.getConnectionInfo();
@@ -335,7 +339,7 @@ public class Utils {
                                 && !addr.equals(vpn_ip)) {
                             String sAddr = addr.getHostAddress();
 
-                            if ((addr instanceof Inet4Address) && !sAddr.equals("0.0.0.0")) {
+                            if ((sAddr != null) && (addr instanceof Inet4Address) && !sAddr.equals("0.0.0.0")) {
                                 Log.d("getLocalIPAddress", "Using interface '" + intf.getName() + "' IP: " + sAddr);
                                 return sAddr;
                             }
@@ -401,9 +405,12 @@ public class Utils {
         };
     }
 
+    // API level 31 requires building a NetworkRequest, which in turn requires an asynchronous callback.
+    // Using the deprecated API instead to keep things simple.
+    // https://developer.android.com/reference/android/net/ConnectivityManager#getAllNetworks()
+    @SuppressWarnings("deprecation")
     public static boolean hasVPNRunning(Context context) {
         ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
-
         if(cm != null) {
             Network[] networks = cm.getAllNetworks();
 
diff --git a/build.gradle b/build.gradle
index fdfc4949..1058a4d9 100644
--- a/build.gradle
+++ b/build.gradle
@@ -6,7 +6,7 @@ buildscript {
         mavenCentral()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:7.0.3'
+        classpath 'com.android.tools.build:gradle:7.0.4'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
@@ -20,7 +20,7 @@ allprojects {
         maven { url 'https://jitpack.io' }
     }
     tasks.withType(JavaCompile) {
-        options.compilerArgs << "-Xlint:deprecation"
+        options.compilerArgs << "-Xlint:unchecked" << "-Xlint:deprecation"
     }
 }
 
diff --git a/submodules/MaxMind-DB-Reader-java b/submodules/MaxMind-DB-Reader-java
index 778acb6f..91325b34 160000
--- a/submodules/MaxMind-DB-Reader-java
+++ b/submodules/MaxMind-DB-Reader-java
@@ -1 +1 @@
-Subproject commit 778acb6fc055547eeb7f214d6903866855bb8887
+Subproject commit 91325b34b13384a36e230b4c6862f46d00015bd1