I have had a few people request my math app to go up to 20 instead of 12. Since I wanted to keep the original to the classic ‘To 12’ math facts, I decided to create a separate app to go up to 20.
The only issue with that app is that you can NOT choose to only go up to 12, you have to go up to 20. If I have enough requests, I will consider updating the app to allow the choice to go up to 12 or go to 20. But this will take some overhaul of the code, so it isn’t the quite change that taking it up to 20 was.