Facebook is apparently working on a brand new mobile app for Apple iOS devices that is being developed from scratch. This new app is being coded using Objective-C which is the native development platform for iOS devices.
The current app is mostly built using web technologies which makes the development process easy but hurts the performance.
Facebook’s mobile app for Android and iOS are both criticized for being buggy and awfully slow. This new update for iOS would probably fix the problem for iPhone users. Remains to be seen if a similar update is planned for Android devices.