Change iPhone system font without jailbreaking using this iOS app: How it works

An iOS developer Zhuowei Zhang (@zhuowei) made an app that allows users to temporarily change their system font without needing to jailbreak their iPhone. He tweeted about the functionalities of his app adding a link to his GitHub page where users can download the app. 

According to his GitHub page, this app works on iOS 16.1.2 and below without the need to jailbreak iPhone. The current version of the app supports fonts such as DejaVu Sans Condensed, DejaVu Serif, DejaVu Sans Mono, Go Regular, Go Mono, Fira Sans, Segoe UI, Comic Sans MS and Choco Cooky (a popular Samsung font).

The iOS developer took advantage of the CVE-2022-46689 security exploit that allowed him to temporary change system fonts. The changes to the system fonts are safe and temporary and the iPhone reverts to its original font after reboot. However, the developer advised people to take a backup of their phones before trying this out. He also invited other developers to make changes to his GitHub code and use it, he also asked other developers to get inspired and tinker with the CVE-2022-46689. 

Zhuowei Zhang in his tweet mentioned that his app only affects some text iOS and is not system-wide. Apart from the fonts available inside the app, the developer has allowed users to import custom fonts provided they are ported for iOS. The developer has so far posted images from Settings, Apple Music, App Store, File Manager, Contacts, Messages, and Weather App showcasing the custom fonts he has applied. 

The app won’t work on iPhones with iOS 16.2 as the security exploit got fixed in the latest update.