What are some useful iPhone hacks that you know?

Jailbreak let you do many thinks, like location spoofing, theme change, and simple say full control over root file.

unfortunately there is no Public  untethered Jailbreak after iOS 9.1 ,

there is partial/semi jailbreak still, Upto iOS 11.1.2 partial jailbreak there till date

1. *#0+80*0001*# - код для взлома сети и трансфомация телефона в робота который убежит от вас ,а потом вернется. Не рекомендую тестировать.2. *102# 

1)Invert display color to browse at night.

2)Charge battery faster in airplane mode.

3)Assistive touch.