SudokuShare is a free Android application.
SudokuShare does not collect any user data.
SudokuShare requires 2 authorizations:
Reading/writing its private file system, This is used to store the puzzles and read them when the application restart. The filesystem can be found on /android/data/bzh.battini.sudokushare/files.
You can read these files and verify the information stored here.
Taking photos when you want to grab a puzzle from a book/screen/newpaper...
The photo is stored in the same file system.
In addition, if you want SudokuShare to send the puzzle to someone, SudokuShare will cann the application you designate for it (e.g gmail, outlook...) and send 1 mail with the puzzle attached. You can read the mail and verify.