I don't think they can tell, my iPhone 3G was jailbroken but I restored it after figuring out I don't use anything on the JB side except custom carrier, so I restored from backup (as I restored the phone normally) and the custom carrier is still there
Nope, it's perfectly fine. A jailbroken phone acts just like a normal phone, but with added control that you can edit what you want and install other apps from Cydia.
Nope, it's perfectly fine. A jailbroken phone acts just like a normal phone, but with added control that you can edit what you want and install other apps from Cydia.