ios - Make it hard to tamper with game data on non-jailbroken devices -

we developing game game logic executed locally (no server back-end) , make difficult tamper game data (such user credits, game settings , on).

now, it's possible on non-jailbroken devices access filesystem , change game data - so, example if user inventory stats stored in plist file, it's easy edit them.

if move game settings plist files source-code files, such compiled binary, require @ least modification of binary change settings. on non-jailbroken phones - modified binaries still run, or apple codesigning prevent modifying binaries in way?

what quick , easy implement measures make bit harder tamper game-data (especially on non-jailbroken phones. optimally we'd provide kind of security @ least require jailbreak make modifications game)?

so - summarize questions:

1. can binary part of ios app modified , still run on non-jailbroken devices?
2. what quick , easy implement measures make harder tamper gamedata on non-jailbroken devices?

you can't modify binary invalidate signature. use sort of encryption on data don't want users modify. can make simple or complex want. don't think ios provides kind of encryption services out of box, don't need go hog wild - simple rot13 algorithm do, since we're not talking password-level security here. if want, can add checksum on encrypted data, invalidate if checksums don't match.