Why don't all great apps detect jailbreak to limit functionality in their app? [duplicate]

Question

Possible Duplicate:
How do I detect that an SDK app is running on a jailbroken phone?

I see there are many ways to detect which device is jailbroken in xcode. How do I detect that an iOS app is running on a jailbroken phone?

I'm undestanding that: I don't want jailbroken device access to my app, so I put my detection code to my project, so all jailbroken device can't use it.

But a lot of paid app can install in jailbroken device (Angry Bird, Fruit Ninja...). Do I missunderstand, or there are some special reason so they don't do this (they want their app is popular...), or before app can be installed in jailbroken device, code of this app can be changed a little (I don't think so)?

Beside this, I see a lot of answer for question "How to detect that device is jailbroken" in this link above. I've found this: http://www.interiders.com/2011/10/26/enable-directv-to-work-on-jailbroken-ipad/

So, what is the best solution for detecting jailbroken device?

Answer 1

Why [don't] (all) great apps use “Detect jailbreak feature” to limit user[s] from their app?

Because why would you intentionally restrict your target market? Money from advertising, app sales, and in-app purchases that comes from jailbroken devices is just as real as the money that comes from non-jailbroken devices. So why would you throw your hand up and say "I want less money"?

What you may legitimately want to do is prevent piracy of your app. But detecting a jailbroken device isn't the same thing as detecting a pirated copy of your app. A jailbroken device can still install apps without pirating them.

Besides, generally speaking there's no 100% foolproof way to prevent piracy, apart from not publishing a desirable app. You'd do better if you focus on making an awesome app that everyone wants and most people pay for, and not worrying about the handful of pirates out there.

As for the "best" way to detect a jailbroken device, the question you linked to has lots of good suggestions:

How do I detect that an iOS app is running on a jailbroken phone?

...try some of them, and see which works best for you.