Just FYI, Tenorshare reiboot fixed my wife’s phone. This is an XS Max that might have gotten slightly wet when handled with wet hands near the pool. It was stuck in the apple logo - reboot cycle. Tried other advice to restore OS using itunes just got it stuck in recovery mode. iTunes failed to restore, giving error 4013. So I tried the tenorshare program to get it out of recovery mode. That worked, and not only that, but the phone is working normally again and all the data was intact. First thing I’m doing (in progress right now): backup everything before it goes on the fritz again.