Q:"My iPhone keeps restarting suddenly. This has gone on for several days and directly affects my use of iPhone, especially when I am having a calling with others or paying online. How can I fix this issue? I'm really upset at present." – Aron
Truthfully as Aron said, that iPhone keeps restarting randomly will bring a series of troubles in a sudden moment. However, you may suffer from it for a number of possible reasons, such as iOS upgrade, hardware problems, faulty apps, etc. Whatever the case is, following tips can be advisable for you.