Remove all Firebase libraries except for those required for messaging

Add Firebase installation ID to "About" section of app
Update privacy policy

CHANGES.md

@@ -1,3 +1,9 @@
+### 0.6.30 ###
+
+* Remove all Firebase libraries except for those required for messaging
+* Add Firebase installation ID to "About" section of app
+* Update privacy policy
+
 ### 0.6.29 ###
 
 * Update dependencies

PRIVACY.md

@@ -1,11 +1,77 @@
-No data leaves your Android device through VoIP.ms SMS except in the following cases:
-* Your VoIP.ms SMS credentials, DIDs, and messages are sent to or retrieved from
-  VoIP.ms.
-* If you have push notifications enabled, VoIP.ms SMS uses Firebase Cloud
-  Messaging and a Cloudflare Worker maintained by me to forward VoIP.ms URL
-  callbacks to your device. This callback is configured to only contain your DID
-  and no other information, such as the text of your messages. This does not
-  apply to the F-Droid version of the app.
-* VoIP.ms SMS collects some non-personally identifiable information through
-  Firebase services which is used for troubleshooting and to improve the app.
-  This does not apply to the F-Droid version of the app.
+# Privacy Policy
+
+This privacy policy is in reference to:
+
+* the app "VoIP.ms SMS", hosted on the Google Play and F-Droid app stores; and
+* the developer "Michael Kourlas".
+
+The purpose of this policy is to comprehensively disclose how the app accesses,
+collects, uses, and shares user data.
+
+### Data collected to implement core app functionality
+
+The app collects and uses:
+
+* your VoIP.ms credentials;
+* the DIDs in your VoIP.ms account;
+* SMS/MMS messages sent or received using VoIP.ms; and
+* metadata associated with each such SMS/MMS message, including the ID
+  assigned to each message by VoIP.ms, the date and time the message was sent,
+  and the source and destination phone numbers.
+
+The app stores this data on your device using the standard mechanisms provided
+by Android for storing app data. You can delete all data stored by the app on
+your device at any time by simply deleting the app.
+
+By using the app, you direct the app to share this data with
+[VoIP.ms](https://voip.ms/), which accesses, collects, uses, and shares this
+data in accordance with its
+own [privacy policy](https://voip.ms/privacy-policy).
+
+The collection, usage, storage, and sharing of this data as described in this
+section is essential to implement the app's core functionality.
+
+### Data collected to implement push notifications
+
+This section only applies to the Google Play version of the app, not the
+F-Droid version of the app.
+
+If you enable push notifications, the app automatically configures your VoIP.ms
+account to
+ping [a web service hosted by Michael Kourlas](https://voipmssms-notify.kourlas.com)
+(the "Push Notification Service") every time you receive an SMS/MMS message.
+
+The Push Notification Service is implemented as a Cloudflare Worker with source
+code [available here](https://github.com/michaelkourlas/voipms-sms-push-notifications).
+The Push Notification Service also uses Firebase Cloud Messaging, a service
+provided by Google.
+
+The app registers all configured DIDs with Firebase Cloud Messaging. These DIDs
+are associated with
+an [installation ID](https://firebase.google.com/docs/projects/manage-installations)
+that is unique to every installed instance of the app.
+
+When you receive an SMS/MMS message, the Push Notification Service provides
+your DID to Firebase Cloud Messaging, which uses it to forward the ping to your
+device. This allows the app to request the new message from VoIP.ms and display
+a notification for it.
+
+The callback URL configured by the app only includes your DID and no other
+information, such as the text of your SMS/MMS messages. The ping simply tells
+the app to check for new messages.
+
+The Push Notification Service does not itself store your DID for longer than
+required to forward the DID to Firebase Cloud Messaging.
+
+Firebase Cloud Messaging will maintain the registration of a DID and its
+association with an installation ID indefinitely. To delete this registration
+and the installation ID, collect the installation ID from the "About" section
+of the app and contact Michael Kourlas for assistance.
+
+The collection, usage, storage, and sharing of your DID as described in this
+section is essential to implement the app's support for push notifications.
+
+## Contact information
+
+If you have any questions or concerns about this policy, please contact
+Michael Kourlas at [email protected].

build.gradle.kts

@@ -11,7 +11,6 @@ buildscript {
 
         // fdroid-remove-start
         classpath("com.google.gms:google-services:4.4.2")
-        classpath("com.google.firebase:firebase-crashlytics-gradle:3.0.2")
         // fdroid-remove-end
     }
 }

fastlane/metadata/android/en-US/changelogs/151.txt

@@ -0,0 +1,4 @@
+0.6.30
+• Remove all Firebase libraries except for those required for messaging
+• Add Firebase installation ID to "About" section of app
+• Update privacy policy

voipms-sms/build.gradle.kts

@@ -9,7 +9,6 @@ plugins {
 
     // fdroid-remove-start
     id("com.google.gms.google-services")
-    id("com.google.firebase.crashlytics")
     // fdroid-remove-end
 }
 
@@ -19,8 +18,8 @@ android {
         applicationId = "net.kourlas.voipms_sms"
         minSdk = 21
         targetSdk = 35
-        versionCode = 150
-        versionName = "0.6.29"
+        versionCode = 151
+        versionName = "0.6.30"
 
         ksp {
             arg("room.schemaLocation", "$projectDir/schemas")
@@ -127,10 +126,9 @@ dependencies {
 
     // fdroid-remove-start
 
-    // Firebase libraries
+    // Google and Firebase libraries
+    "primaryImplementation"("com.google.android.gms:play-services-base:18.5.0")
     "primaryImplementation"(platform("com.google.firebase:firebase-bom:33.8.0"))
-    "primaryImplementation"("com.google.firebase:firebase-analytics-ktx")
-    "primaryImplementation"("com.google.firebase:firebase-crashlytics-ktx")
     "primaryImplementation"("com.google.firebase:firebase-messaging-ktx")
 
     // fdroid-remove-end

voipms-sms/src/fdroid/kotlin/net/kourlas/voipms_sms/utils/fcm.kt

@@ -20,6 +20,13 @@ package net.kourlas.voipms_sms.utils
 import android.content.Context
 import androidx.fragment.app.FragmentActivity
 
+/**
+ * Stub for F-Droid builds.
+ */
+fun getInstallationId() {
+    return "Not supported"
+}
+
 /**
  * Stub for F-Droid builds.
  */

voipms-sms/src/main/kotlin/net/kourlas/voipms_sms/preferences/fragments/AboutPreferencesFragment.kt

@@ -18,8 +18,12 @@
 package net.kourlas.voipms_sms.preferences.fragments
 
 import android.os.Bundle
+import androidx.lifecycle.lifecycleScope
 import androidx.preference.PreferenceFragmentCompat
+import kotlinx.coroutines.launch
 import net.kourlas.voipms_sms.R
+import net.kourlas.voipms_sms.utils.getInstallationId
+import net.kourlas.voipms_sms.utils.preferences
 
 class AboutPreferencesFragment : PreferenceFragmentCompat() {
     override fun onCreatePreferences(
@@ -29,4 +33,17 @@ class AboutPreferencesFragment : PreferenceFragmentCompat() {
         // Add preferences
         addPreferencesFromResource(R.xml.preferences_about)
     }
+    override fun onResume() {
+        super.onResume()
+
+        lifecycleScope.launch {
+            val firebaseInstallationId = getInstallationId()
+
+            for (preference in preferenceScreen.preferences) {
+                if (preference.key == getString(R.string.preferences_about_firebase_installation_id_key)) {
+                    preference.summary = firebaseInstallationId
+                }
+            }
+        }
+    }
 }

voipms-sms/src/main/res/values/strings.xml

@@ -130,6 +130,8 @@
     <string name="preferences_about_privacy_title">Privacy</string>
     <string name="preferences_about_third_party_embedded_title">Third-party notices (embedded code)</string>
     <string name="preferences_about_third_party_packages_title">Third-party notices (packages)</string>
+    <string name="preferences_about_firebase_installation_id_title">Firebase installation ID</string>
+    <string name="preferences_about_firebase_installation_id_key" translatable="false">installation_id</string>
 
     <!-- Markdown -->
     <string name="preferences_markdown_extra">net.kourlas.voipms_sms.MARKDOWN_DOCUMENT_TYPE</string>
@@ -400,7 +402,7 @@
 
     <!-- MISCELLANEOUS -->
     <string name="app_name">VoIP.ms SMS</string>
-    <string name="copyright">Copyright © 2015–2024 Michael Kourlas</string>
-    <string name="version">Version 0.6.29</string>
+    <string name="copyright">Copyright © 2015–2025 Michael Kourlas</string>
+    <string name="version">Version 0.6.30</string>
     <string name="toast_error">Error: %1$s</string>
 </resources>

voipms-sms/src/main/res/xml/preferences_about.xml

@@ -73,4 +73,7 @@
                 android:value="PACKAGE_LICENSES" />
         </intent>
     </androidx.preference.Preference>
+    <androidx.preference.Preference
+        android:key="@string/preferences_about_firebase_installation_id_key"
+        android:title="@string/preferences_about_firebase_installation_id_title" />
 </androidx.preference.PreferenceScreen>

voipms-sms/src/primary/kotlin/net/kourlas/voipms_sms/utils/exceptions.kt

@@ -18,15 +18,11 @@
 package net.kourlas.voipms_sms.utils
 
 import android.util.Log
-import com.google.firebase.crashlytics.FirebaseCrashlytics
 
 /**
  * Log the specified exception.
  */
 fun logException(e: Exception) {
     // Log the exception locally
     Log.e("logException", "exception", e)
-
-    // Log the exception remotely as well using Crashlytics
-    FirebaseCrashlytics.getInstance().recordException(e)
 }

voipms-sms/src/primary/kotlin/net/kourlas/voipms_sms/utils/fcm.kt

@@ -21,7 +21,9 @@ import android.content.Context
 import androidx.fragment.app.FragmentActivity
 import com.google.android.gms.common.ConnectionResult
 import com.google.android.gms.common.GoogleApiAvailability
+import com.google.firebase.installations.FirebaseInstallations
 import com.google.firebase.messaging.FirebaseMessaging
+import kotlinx.coroutines.tasks.await
 import net.kourlas.voipms_sms.BuildConfig
 import net.kourlas.voipms_sms.R
 import net.kourlas.voipms_sms.notifications.Notifications
@@ -30,6 +32,13 @@ import net.kourlas.voipms_sms.preferences.didsConfigured
 import net.kourlas.voipms_sms.preferences.getDids
 import net.kourlas.voipms_sms.preferences.setSetupCompletedForVersion
 
+/**
+ * Retrieves the Firebase installation ID.
+ */
+suspend fun getInstallationId(): String {
+    return FirebaseInstallations.getInstance().id.await()
+}
+
 /**
  * Subscribes to FCM topics corresponding to the currently configured DIDs.
  */