Following my post on what to do if your WatchOS update is stuck, I've been receiving questions about what to do when your iPhone is stuck trying to install iOS 13. Don't worry, there is a fix!
Common symptoms are when the update screen seems stuck on "Estimated Time Remaining," "Update Requested," or "Verifying Update," or "Preparing to Update."
Read more: Call and battery problems plague iOS 13.1.2
There first "fix" is patience. Just wait.
Go for a cup of tea or coffee, watch a movie, or just go for a walk (none of these things need an iPhone in hand to do… honestly!).
Most of the time just waiting for fixes these problems.
Another "fix" is to move to a spot with stronger Wi-Fi or cellular signal. This can be quite effective when the download just doesn't want to come in.
Neither of those work?
Time to get a bit more hands-on and delete the download and redownload it.
Go to Settings > General > iPhone Storage (or iPad Storage) and find iOS 13 in the listing. Tap on it and select Delete Update, and then confirm the deletion.
Afterwards, I recommend rebooting your device (reboot instructions here), and then go to Settings > General > Software Update to redownload the update.