My iPhone 7 Plus won't boot up. It just keeps flashing up the apple logo, then going black. I've tried restoring and updating through iTunes, but it hasnt worked. What can I do?
When you say you have tried to restore and update through iTunes is that putting the phone in Recovery Mode.
See section: If your device turns on but gets stuck during start up
because if that didnt work then I'd say its something wrong with a component in the iPhone.
Might need to look at scheduling a call back from Apple (or chat with them) but they will no doubt take you through the same process that I think you have already gone through.
If its still under gaunentee then you should be able to take it back to the store.
If not then it could be sent to Apple to be fixed/looked at.