Apple Users

I bought an iPad and it said to put the iPhone next to it and all the settings got transferred.

But I do advise making a backup just before doing anything, however you want to do that, iCloud backup or to a computer.

Why? because stuff happens.

I ran the 15.6.1 upgrade and it partly bricked my phone. I couldn't reset it from Control Panel.

So, I figured how to reset it in iTunes. Then recovered data from my most recent backup to the mac.

I regularly copy all photos and downloads to the computer because it's easier to manage them there. And the screen is (ahem) vastly larger.

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If you are using iTunes, please have the latest version of it. I have had new phones refuse to read the older phone's backups because "This phone won't work with your version of iTunes".

and P.S. 15.6.1 works ok. The upgrade must have been corrupted somehow. Just my luck.
Stuff happens.
Good luck.