Android memory is just like a flash drive. The files are still there, just invisible and flagged to be written over the next time it needs that space. You may not even need to need to unlock the bootloader to recover your data using any legit file recovery program. Just do it now or your recovery chances start dropping fast with every app you redownload and install over the old data.
Piriform makes a great free file recovery program called Recuva. Connect your phone to a computer and tell Recuva to search whatever drive letter your app data is usually stored on and remember that there are usually only 2 places it could be: Internal memory or an external memory card. You may have to put your phone in developer mode or USB storage mode if either of those settings exist in your Android.