iOS Jailbreaking has been a controversial topic for the last decade, since it’s release. The main purpose it serves is that it removes most of the limitations set by Apple, making any device vulnerable to different changes, such as theming the app icons, importing different features for newer models or even connecting and manipulating a foreign WiFi network.
The main cause of this being a controversial topic is that it has been considered illegal for a long time, causing different beliefs of causing data leaks, viruses and hackers attacks and paranoia among most of the typical iOS users.
As FBI and Apple analyze showed that this should not be considered illegal in any state but this is a warning signal, as removing the security and limitations set by Apple (which are set to protect all its users) could cause a massive impact and harm on the device, depending on who access it.
Even the jailbreak community from Reddit insists that installing the modifications (so called tweak) from piracy repositories could create irreversible damage to iPhone and even mentioning one of those repositories is prohibited among their community rules and not encouraged at all.
They also claim that using the tweak from the well-known and the most trusted developers will keep your phones safe and not give you any reason to worry about it.
A study conducted by one of the jailbreak developers showed that the iPhone’s vulnerability caused by removing the files may be exploited in many ways, and demonstrated how easy it is to manipulate a jailbroken device from distance, using a command line or a Terminal. Doing this could grant anyone full acces to a jailbroken iPhone, from uploading malwares and key loggers to full acces to iCloud sensitive informations such as Keychains or payment method informations.
On the other hand, some sources claim that jailbreaking and keeping it under control could cause a massive privacy boost on the iPhone itself, due to the various tweaks designed to help the user protect its data. For example, one of those consist in detecting when an app is requesting personal data from the phone and giving it fake informations about it, keeping our real informations secure.