I consider that state of the art and brand new. I just inherited an iPhone XS and the battery is at 91%. I figure I can go at least another 3 years. For reference I was using a Oneplus 3T which is still going strong.

Just recently replaced my XS Max battery. Great phone! :)

It is indeed the most comfortable of the phones in the last decade perhaps. I am still rocking it. Recently my battery died and they replaced it but that battery too wouldn’t charge for hours and then would charge by a trickle. They said they’d just replace my phone so now I have a brand new XS max ready for another 5 years.

I use an Xs Max to test iOS 18.

Works great. Original battery.

I used the same OnePlus 3T that I bought used, until it was stolen. Would have probably considered a new OnePlus but all their models were too big and expensive at the time, so went Pixel 7 near the end of the cycle. Even though I've been a mac user for about 12 years, iPhones have never made it into the realm of consideration.

I have that same phone and have been using it now for six years, and according to the battery health in the settings, the battery is still in good shape, there’s no notice of it being degraded.

I’m not saying you’re making the wrong move, but if you’re willing to go with a carrier like ATT, you can get $1000 trade-in value for that iPhone 13 Pro towards a new iPhone 16 Pro. You can even just buy an unlocked iPhone 12 off of eBay (for about $250) and get the same $1000 trade-in credit for you son. There are some caveats. For example, the credits are paid out evenly over 24 months, but if you plan to keep it for 2 years, you basically get a $250 iPhone 16 Pro.

Again, it might not be the right decision for you, but I thought you might like to be aware of the option.

You'll end up paying for it in the backend with their over priced plans

Tmo normally had good trade ins also, and has the lowest plan prices of the big 3

I've tended to buy iPhones that are 2 or 3 generations old from eBay and Swappa for my family and use Mint or Tello for cheap cellular service. Our costs might be $350 for a phone and $100 - $150 per year for service.

We do get them a nice new phone when they graduate high school.