TeMapihi Said:
"Downloading and Installing 16.4: My phone keeps crashing. It is trying to download and install 16.4 (for the last four days) and hasn't done it. The phone keeps randomly crashing in the middle of phone calls, txt messaging or listening to music. It then closes right down and re-opens."
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Updating Using a Computer and Ethernet:
Have a Computer Handy? If so, try using a computer to update. Go here: Update your iPhone Using a Computer - User Tip. If any updates are availabe, they will install, sure enough.
Use Ethernet:
If WiFi is so unsuccessful, then you can try connecting your computer to Ethernet, while performing the update on it.