Apple is sternly saying, "Don't jailbreak!" Most of what Apple says above is accurate. I jailbroke my original iPhone back in 2007, and experienced a lot of the issues noted above. Instability was perhaps the biggest issue, especially if you install a lot of unapproved applications. I didn't see too much of the dropped calls, but visual voicemail definitely became disabled.
As designed by Apple, the iPhone OS ensures that the iPhone and iPod touch operate reliably. Some customers have not understood the risks of installing software that makes unauthorized modifications to the iPhone OS ("jailbreaking") on their iPhone or iPod touch. Customers who have installed software that makes these modifications have encountered numerous problems in the operation of their hacked iPhone or iPod touch. Examples of issues caused by these unauthorized modifications to the iPhone OS have included the following:
Apple strongly cautions against installing any software that hacks the iPhone OS. It is also important to note that unauthorized modification of the iPhone OS is a violation of the iPhone end-user license agreement and because of this, Apple may deny service for an iPhone or iPod touch that has installed any unauthorized software.
- Device and application instability:Frequent and unexpected crashes of the device, crashes and freezes of built-in apps and third-party apps, and loss of data.
- Unreliable voice and data: Dropped calls, slow or unreliable data connections, and delayed or inaccurate location data.
- Disruption of services: Services such as Visual Voicemail, YouTube, Weather, and Stocks have been disrupted or no longer work on the device. Additionally, third-party apps that use the Apple Push Notification Service have had difficulty receiving notifications or received notifications that were intended for a different hacked device. Other push-based services such as MobileMe and Exchange have experienced problems synchronizing data with their respective servers.
- Compromised security: Security compromises have been introduced by these modifications that could allow hackers to steal personal information, damage the device, attack the wireless network, or introduce malware or viruses.
- Shortened battery life: The hacked software has caused an accelerated battery drain that shortens the operation of an iPhone or iPod touch on a single battery charge.
- Inability to apply future software updates: Some unauthorized modifications have caused damage to the iPhone OS that is not repairable. This can result in the hacked iPhone or iPod touch becoming permanently inoperable when a future Apple-supplied iPhone OS update is installed.
You can't blame Apple for taking this stance, though it is a bit onerous. Situations such as the Great Google Voice Debacle of 2009 are enough to push users over the edge and convince them that jailbreaking is the way to go. Granted, not many other mobile platforms have 50,000 applications available to them at the moment, so I think it is a little weak for iPhone users to claim "lack of choice."
Do these arguments make sense in Apple's case against the Electronic Frontier Foundation? That's for lawyers to decide. In the mean time, remember that Apple is in control. Not you.