According to the specifications, the TonePrint App should work with Android version 5 and up.
I have a Huawei smartphone running on Android 6 version.
When I try to upload the TonePrint Application from the Google Play I get the message my smartphone is not compatible with the current version.
Tried the same with a Samsung device and got the same message.
What an unpleasant surprise.
We should not consider a 3 year old smartphone Vintage.