Download the .apk on your phone and open it.
If Android asks, allow your browser or Files app to install unknown apps.
Before updating, open Settings > Account and wait until it says Synced. If an upload warning is showing, wait for it to clear too. Let any import or image add finish.
Install the new .apk over the old one. Do not uninstall first: uninstalling removes the copy on your phone, and unsynced changes are lost.
Install and update on Android
How to install Oknola on an Android phone and update it without losing changes.