Supports Android 23 through 33. QRS detection uses a new algorithm. The HR/RR plot has been enhanced. You can optionally see a plot of the QRS algorithm.
You will need to change Settings on your Android device to allow Unknown Sources to install the APK. Google is making it harder to side load APKs, so you may have to experiment depending on your version of Android. My Files seems to work.
The APK is in the zip. It will show on the device as KE.Net ECG 3.2.1. (3.2.1 and 3.2.2 are the same.)