Does Jailbreak have any impacts to iOS development?

Question

It is very easy to jailbreak ios device today, but I am not going to figure out how to do that here.

I want to ask , is there any influence for normal ios development if the test devices are jailbreaked ?

My simple answer will be "NO".

But I am not sure what is really happened for jailbreak devices. So question here for more serious answers. Thanks

Answer 1

Basic development work, just like any other device and so it should be safe to use it. The problem is that the jailbreak (not tweaks, the jb itself) modifies some core components of the system (namely some subtle sandbox things). It can happen that things that shouldn't work at all suddenly work on jailbroken devices because of these changes (not to talk about all the tweaks you could have installed that can change lots of things).

So, you can definitely use a jailbroken device to develop (after all not everybody can afford a dedicated device for development), but be sure to thoroughly test your app on a vanilla device or you can have bad surprises.

@H2CO3 I can't comment yet, but I think you missed the point: he didn't ask about running apps on jailbroken devices, but to test apps on jailbroken devices (which is a pretty bad idea).

Answer 2

Basically, jailbreaking doesn't have any negative impacts at first glance, at the "works - doesn't work" level. Being a jailbroken developer myself, I can confirm that practically everything that (technically) works on a non-jailbroken device works on a jailbroken one too. Jailbreaking doesn't abandon APIs, doesn't remove software or system components that are needed for running an official application. It only brings additional facilities and features to extend the opportunities of developers (and thus that of users as well).

However, given that jailbroken systems are almost completely open, there are security-related considerations to be made. Specifically:

1. Your app can be cracked. And by some people, it will. Be aware of it. There is (was) Install0us, there's In-App Purchase cracker, etc. If you don't care, that's just fine, though: only a small portion of iOS users jailbreak their devices, and not each and every jailbreaker is a pirate whose only intention is to steal your app!

2. Sensitive data can be obtained from the device. If you aren't careful enough, two possible things may happen. Either you store some sensitive user data on the filesystem (even the Keychain is insecure on jailbroken devices!) and somebody else can view it (effectively enabling identity theft), or your app can be hacked (imagine if you store the score of a user in a game in a plist file, and the user simply overwrites the value in the plist to cheat).

3. The behavior of your application can easily be altered using the MobileSubstrate framework - something that you may or may not want :)

All in all: beware of cheaters and crackers, but still don't punish innocent users! Popups saying "This app doesn't run on jailbroken devices" are unfair and decrease your reputation as a developer.

Answer 3

It only won't work if you have installed something that would effect any frameworks or services as @Flash84x said.

Apart from that you are fine.

Answer 4

there is one big problem that I've took more than a week to figure out:

inAppPurchase development doesn't work on JB devices (it gives InvalidProductIDs for all inApps)

(some reports say it's for JB with AppSync installed)

Answer 5

It depends what is installed, if you start adding some of the packages that are hooks of the foundation services you could possibly see some strange/unpredictable activity. Other than that I think you should be fine, the JB community all develop and test their apps on JB devices so I would think generally you are fine.