Write to support@cypresstech.net. Please include the app name, the version from Settings → About, your phone model and what happened. The full rules are in the app at Settings → How to play.
They are the runs of filled squares in that row or column, in order. "3 1" means a run of three, then at least one blank, then a single square.
No. Every puzzle can be finished by reasoning about one row or column at a time, and has exactly one answer.
At midnight on your phone. It is made on the phone from the date, so it works offline.
Settings → Remove ads. It is a one-time purchase, not a subscription, and it removes every ad. It does not unlock anything else, because nothing else is locked.
Open Settings → Restore purchase while signed in to the Google account you bought it with. If the price does not show, check that you are online and that Google Play is up to date.
No. The game screen never shows an ad. The free version shows a banner on menu screens and may show one full-screen ad after a game has finished.
Yes. Every part of the game works with no connection. Ads simply do not appear.
Only on your phone. There is no account and no cloud copy, so they do not move to a new phone and are erased if you uninstall.
No. The game is saved after every move. Open the app and tap Continue.
Starting a new game while one is in progress ends the old one and records it as a loss.
Where a consent choice applies to you, Settings → Privacy choices opens the form again.