Months ago I downloaded your version of simply piano on my mobile phone and it suited me perfectly.
Today I have tried to install it on my new Galaxy tab7. I've tried it several times, and it always ends up giving an error.
Sometimes it gives the error at the beginning, and on other occasions if it lets you do some exercises, but when it reaches the rhythm, it returns the error and no longer lets continue, because to continue you have to have done the previous exercises first.
The error is always the same: no internet access.
I have verified that the tablet does have internet access, and the rest of the apps do work, so I think it is up to the designer to avoid using hacked premiums.
Could you fix it? It would be great if you could, because it is a very good but very expensive app.