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README.md

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 Android releases for [Joplin](http://joplin.cozic.net)
 
 This repository only hosts the Joplin APK files. The source code is at /~https://github.com/laurent22/joplin and the Google Play page at https://play.google.com/store/apps/details?id=net.cozic.joplin
+
+You should assume that most of these releases are [pre-release](https://joplinapp.org/help/about/prereleases/) unless it is marked as "latest".
+
+## Choosing the right version
+
+If you do not know your phone's architecture, you can find out what it this way:
+
+- Install a Terminal app such as **termius**
+- Run this command: `adb shell uname -m`
+
+The reply will tell you what architecture the Linux kernel in your Android OS is running. It tells you this in Linux terminology, rather than Android ABI names:
+
+- "aarch64" is "arm64-v8a" ABI.
+- "armv7l" is "armeabi-v7a" ABI.
+- "x86_64" is "x86_64" ABI.
+- "i386" or "i686" is Android's "x86" ABI.