This app needs a lot of work. I would not buy it again, nor would I suggested anyone else getting it. I kept downgrading it from 4 stars to 1 star, as I kept encountering problems. Initially, this appeared to be a great app to help me with my times tables, but I came across too many problems with it. 1) The “specific number chooser” doesn’t work. I need more practice on my 3s - 9s, not zeros and 10s. 2) If you get the wrong answer, you have to delete the numbers before entering in a new answer. It should automatically delete the entry on a wrong answer, so you don’t waste time deleting numbers. 3) You can’t adjust the time frame of the testing. 4) The app closes every time I want to start a new test. Even after turning phone off & on again. 5) The Leaderboard shows only the top 20, even though it states “Top 50”. 6) And, after paying for the app, finding out it’s flaws, then uninstalling and reinstalling it, it downloads the unpaid-ad version, forgetting that I had already paid for it.