The old version was built for Android 6.0 (Marshmallow) to Android 9 (Pie). If you are running Android 12, 13, or 14, the old version will install, but you will face issues:
If you visit the Google Play Store today, you will find the latest Bagan Keyboard. It has a modern Material Design UI, emoji support, and predictive text. So, again, why do people want the Bagan keyboard old version? bagan keyboard old version
Technically, yes, but with significant effort and risks: The old version was built for Android 6
Recommendation for legacy users: Keep a virtual machine (VMware, VirtualBox) with Windows XP for accessing old Bagan documents. Do not use it for new content creation. Recommendation for legacy users: Keep a virtual machine
What makes the legacy Bagan keyboard so special? Here are the defining characteristics: