What's a good jailbreaking app for an iphone?

I have an iphone 4 and want to switch from sprint to a different carrior.what's the best app to do a jailbreak with

1) Jailbreaking an Iphone and Rooting a Android require computer programs, not a app. Go to Jailbreakme.com, youtube.com, google.com. Your jailbreak depends on your Iphone make/model, ios verison, and baseband. Do the wrong jailbreak and its bye bye bye iphone. LMFAO!

#2) Jailbreaking an Iphone and Rooting a Android is not required when flashing a CDMA phone from one CDMA carrier to another. The only things requires is 1) CLEAN ESN and 2) the recieiving carrier acknowledging your deivce and allowing you to use that device on their network

#3) CDMA Iphones won't work on GSM carriers in the USA. There's no hack. So don't even try. But heeh, if you find away, be sure to tell us techies.

#4 Verizon/Sprint/Altell/Virgin/Metro/Crick… Will NOT allow another carrier's iphone on their network. You can try. More power to ya… But i bet my family inheritance they will laugh at you… And say "oh hell no!"

Gotta love Apple Communisism in regards to carrier contractual agreements with eachother. Good thing Android isn't like that!

Another person that assumes jailbreaking is what is needed, when it is not. What you want to do is unlock. Jailbreaking is something else entirely.

As far as doing a jailbreak it depends on which iPhone you have & what version of iOS it is running.
As far as doing an unlock again it depends on which iPhone, what iOS is it running & what baseband it is on.

In this case though you'd be pretty limited. You have a CDMA iPhone, which needs to be flashed, not unlocked & even if you do get through your choices are not as broad as a GSM model.