Update install-android.md: Installation via Obtainium, and DeGoogle notice

docs/guides/install-android.md

@@ -2,26 +2,50 @@
 
 ## Non-Google Play sources
 
-### Installation via Side-loading
-Side-loading means installing manually downloaded APK files on Android (outside official stores).<br />
-You must follow the [installation notes](#installation-notes) for this process.
+### Installation via Sideloading
+Sideloading Android apps involves installing APK files from sources outside official stores. Apps like Obtainium automate APK downloads for the latest versions, avoiding issues with manual methods such as lengthy repeated downloads/installations and missed updates.
+
+To sideload successfully:
+* The first time you attempt to install an APK via an app (e.g. via any file manager, or Obtainium), enable the [install unknown apps](#install-unknown-apps) permission for it. This step is straightforward, and most Android users can complete it without consulting the detailed instructions.
+* If Play Protect warnings appear on Android, follow the installation notes for [allowing APK installations blocked by Google Play Protect](#allowing-apk-installations-blocked-by-google-play-protect). This step is more complex and should be read carefully to ensure success on all Android devices.
 
 #### From RetroArch.com Downloads
+
+#### Installation via Obtainium (recommended)
+"Obtainium allows you to install and update apps directly from their releases pages, and receive notifications when new releases are made available." - Obtainium
+
+Obtainium installs the latest stable RetroArch APK — whether 32‑bit, AArch64, or Universal — directly from https://buildbot.libretro.com/stable/CURRENTVERSIONNUMBER/android/, the same source used for manual downloads. The only difference is that Obtainium automates this process and provides update notifications, helping users stay current and avoid reporting issues from outdated versions. It’s also worth noting that Obtainium is Android TV–friendly, making it suitable for use across all Android devices.
+
+To install RetroArch from Obtainium, follow these steps:
+
+* Install [Obtainium](https://f-droid.org/en/packages/dev.imranr.obtainium.fdroid/) from F-Droid.
+* Add RetroArch to Obtainium
+  * Visit https://apps.obtainium.imranr.dev/.
+  * Search for "RetroArch".
+  * Select “Add to Obtainium” for either RetroArch (32-bit), RetroArch (AArch64), or RetroArch (Universal).
+* Import and Install
+  * When the “Import app” prompt appears, tap **Continue**.
+* Open the newly added RetroArch entry.
+* Tap **Install** to download and install the app.
+
+##### Manual Downloads
 ___
 1. Visit the retroarch.com [Downloads page](https://www.retroarch.com/?page=platforms) and select **Download Stable** or **Download Nightly**.
 2. Open the downloaded APK (via a file manager if your browser does not prompt you when the download is completed).
 3. Select Install.
 
-##### From Buildbot Archives
+###### From Buildbot Archives
 ___
-All [stable](https://buildbot.libretro.com/stable/{{ unit.stable }}/android/) and [nightly](https://buildbot.libretro.com/nightly/android/) bundles are available via BuildBot If you need a specific architecture or build for testing. Builds are named with an architecture suffix: `aarch64` is a 64-bit build, `ra32` is a 32-bit build, and no suffix is a universal build that opts for 64-bit if your system supports it.
+All [stable](https://buildbot.libretro.com/stable/CURRENTVERSIONNUMBER/android/) and [nightly](https://buildbot.libretro.com/nightly/android/) bundles are available via BuildBot If you need a specific architecture or build for testing. Builds are named with an architecture suffix: `aarch64` is a 64-bit build, `ra32` is a 32-bit build, and no suffix is a universal build that opts for 64-bit if your system supports it.
 > 32-bit support on Android is slowly being phased out by the industry, but these builds remain available for older devices or specific use cases.
 
-### Installation via F-Droid
+### Installation via F-Droid (incomplete)
 ___
-RetroArch's most recent stable release can be found [in the F-Droid repository](https://f-droid.org/packages/com.retroarch/) for easier automatic updating.
+The F-Droid release of [RetroArch](https://f-droid.org/packages/com.retroarch/) offers the recent stable release can be found in F-Droid for easier automatic updating.
 
-### (NOT RECOMMENDED) Installation via Google Play
+Note that the F-Droid package lacks many resources ([GitHub issue #16126](https://github.com/libretro/RetroArch/issues/16126); see also [F-Droid RFP #1933](https://gitlab.com/fdroid/rfp/-/issues/1933#note_1731005305)). Both issues are now closed but the resource problems persist.
+
+### Installation via Google Play servers (obsolete)
 ___
 RetroArch is available on the Google Play Store, but has not been updated for years due to Play Store policy changes. You may choose to use this older version, but it is not recommended.
 
@@ -31,35 +55,42 @@ RetroArch is available on the Google Play Store, but has not been updated for ye
 
 A more detailed difference between the Play Store versions can be found in [this libretro blog post](https://www.libretro.com/index.php/retroarch-android-new-versions-for-play-store-please-read/).
 
-# Installation notes
+DeGoogle notice: Google Play requires sign-in with a Google account. Aurora Store offers a free alternative enabling anonymous downloads and updates from Google Play servers without a Google account. [Aurora Store](https://f-droid.org/en/packages/com.aurora.store/) is avalible in F-Droid.
+
+## Installation notes
+
+### Sideloading
 
-## Side-loading
+#### Install unknown apps
 
-* Android may tell you that `the app doesn’t have permission to install APKs`. Click the available `Settings` button in that prompt.
-* In the next menu, turn on the toggle allowing the app install APKs.
+The first time you attempt to install an APK via an app (e.g. via any file manager, or Obtainium), Android displays a prompt: `For your security, your phone currently isn't allowed to install unknonw apps from this source. You can change this in Settings`.
+* Click the available `Settings` button in that prompt.
+* In the `Install unknown apps` menu, toggle on `Allow from this source` to permit the app to install APKs.
 * `Hit the back button` to return to your installation.
 
-## Allowing APK installations blocked by Google Play Protect
+#### Allowing APK installations blocked by Google Play Protect
 
 To install RetroArch from non-Google Play sources (F-Droid, retroarch.com, etc), ensure Google Play Protect either approves it or disable the service entirely.
 
-### Method 1: "Install anyway" in Google Play Protect
+##### Method 1: "Install anyway" in Google Play Protect
+
+This procedure must be repeated each time you sideload an app:
 
 ![google-play-protect_-_install-anyway-1.png](../image/guides/google-play-protect_-_install-anyway-1.png)
 
 ![google-play-protect_-_install-anyway-2.png](../image/guides/google-play-protect_-_install-anyway-2.png)
 
-* When you select “Install anyway”, Google Play Protect will ask you to authenticate your identity. For security reasons, this step cannot be captured in a screenshot, which is why it's described here instead. If Play Protect still fails to install the app even after you’ve entered the correct password, you’ll need to disable Google Play Protect. For instructions, see [Method 2: Disable Google Play Protect](#method-2-disable-google-play-protect).
-
-### Method 2: Disable Google Play Protect
+When you select “Install anyway”, Google Play Protect prompts for identity authentication (password or fingerprint). For security reasons, this step cannot be screenshotted, so it's described textually here. This method requires no Google account—unlike [disabling Google Play Protect](#method-2-disable-google-play-protect), needed if authentication still fails after entering the correct password.
 
-If Google Play Protect still blocks the app installation even after you entered the correct password in Method 1 (a common issue on older Android versions), you'll need to temporarily disable Play Protect to proceed.
+##### Method 2: Disable Google Play Protect
 
-Disable Google Play Protect:
-* Open the Play Store app first
-* Tap your profile icon
-* Select Play Protect
-* Tap the gear icon in settings
-* Toggle off "Scan apps with Play Protect"
+If Google Play Protect still blocks the app installation even after you entered the correct password in Method 1 (a common issue on older Android versions), you'll need to disable Play Protect to proceed.
 
-Once disabled, install the APK — Play Protect will no longer interfere with the process.
+* Open the Google Play Store app.
+* Tap the menu icon in the top right corner.
+  * You don’t need to be signed in to adjust Play Protect settings. But if you’re signed in to a Google account, An icon will show the first letter of your name (for example, “F” for “Foo”) instead of a hamburger button.
+* Tap "Play Protect".
+* Tap the gear icon (Settings).
+* Toggle off "Scan apps with Play Protect".
+* Install the APK — Play Protect will no longer interfere with the process.
+* Android may prompt you to enable Play Protect each time you sideload an APK; always select "No" to maintain this habit.