Long story short yes you want your Iphone/ipod touch jailbroken. You can do away with paying apple for apps and if you unlock it can get rid fo att's horrible service. I for one can say I've never had a problem with att but others seem to have nothing but bad things to say. It used to be if you jailbroke your phone you would run the risk of turning it into a $300 brick but today any problems you run into you can just do a clean restore, just make sure to do a back up before jailbreaking and currently there's no untethered jailbreak for 4.2 or 4.2.1 so if you really want to don't upgrade past 4.1. To sum it up I could go into the legalities of why you shouldn't but I don't think your concerned about that or I could say it voids your warranty but a quick restore will cover your tracks. The real question is do the benifits outweigh the moral dilemma?

Originally Posted by meka

I wonder it's good to jailbreak the iPhone 4?
The pros and the cons?

Let me ask you a question: Why do you want a jailbroken iPhone? If you can answer that, you'll have a better idea if it's worth your while to jailbreak it. For my part, I left my 3GS in jail. For what I needed it to do, 99-cent apps have been working just fine. One less thing to worry about.

I think it is good if you unlocked it, more games and application could be install.

I'd love to get some kind of PDA/Phone/MP3 player, but was leaning more towards something like an HTC Touch or something else I could run Android on. Of course, I've got to admit that iPhone's are nice — every type I've used one I've been impressed by it's UI.

I wonder it's good to jailbreak the iPhone 4?
The pros and the cons?