Keeping XML files in iPhone apps safe from jailbreak?

Question

As you may know, jailbreaking allows you to access the directories of apps that iPhone developers make.

For example, there are many websites that show people with jailbreaks the file path of some of the XML files in fieldrunners app. After changing these you can change nearly anything and make each paid weapon free.

I was thinking about using XML files in an iPhone app I'm making but I'm worrying about people changing them.

Is there any way I can use these files while keeping them secure? Has anyone had any experiences with this?

Answer 1

Basically, the problem gets reduced to "how can I store secret data on a PC" - because a jailbroken iphone gives you as much access as you have on your own box.

There's a variety of answers here, and none of them are "perfect"; you probably know of DRM (digital rights management) attempts on a PC - almost all of them get broken. Now, in case of games, it is pretty compelling to get paid weapons for free, but it's not like it's a million-dollar thing. So you can use the "lock that protects from honest people". For example, add a checksum to your XML file; add a tiny bit of logic to your application code that looks at the XML file and sees if it was tampered with.