Anytime a large amount of people buy a new phone at the same time you see the same thing on social media: complaints about overheating the first day people are using it.
It can be discouraging because you just spent a lot of money and were told how great it was, yet when you use it, you're told it needs to shut down because it is too hot. Of course, the bickering and finger-pointing that accompanies anything posted to social media doesn't help.
The good news is that nothing is wrong, and this should be expected on the first day (and maybe the second day), even if you're using your new phone inside and with air conditioning. It may seem crazy, but a notice that things are too hot means everything is working the way the company that made your phone intends.
Why it happens
When you first sign into your phone, especially if you've restored a bunch of data from a previous one, your phone is working harder than it ever will at any other time. Your network is running full tilt, the phone is copying files nonstop, and system data is written in large bunches. If you pick it up while it is doing all this and mess with wallpapers, widgets, and icons, or even worse — try to play a game or browse the web — it's too much for the phone's processor to handle.
Only so much heat can be moved away from the chips inside your phone. As your using it heat is being created. When more heat is created than can be moved away, you're warned or the device may even shut down so that the chip inside isn't damaged. When it cools down a bit, things will go back to normal.
Because your phone is writing and indexing a large amount of data while it's first set up, almost any other interaction can cause it to get too warm.
It's worse than it used to be
The time you see the most people worrying about phone thermal issues is when a new iPhone is released. Especially the last two models, and there's a reason for that; it ties into why the problem seems worse than it used to be.
It seems worse because it is. Manufacturers are convinced that phones need to be very thin and very fast, with a glass front that covers almost all of the phone's surface. As new phones become thinner and chips become faster, removing that excess heat becomes harder.
When you build a phone using titanium (like the last two iPhones), the problem is compounded. Titanium is a very poor conductor of energy. Using it will make it so you don't notice how hot your phone is getting because more heat is trapped inside.
When the front is glass, and the rear is titanium, the phone will get hotter. Apple quickly sent out a software patch that helped regulate the processor temps for the iPhone 15, and it may do the same for the iPhone 16. Apple can't be expected to know how things will react until the phone is in millions of hands.
This doesn't mean titanium is bad it simply means it is different. It has different properties and requires a different cooling system for a very fast chip. That system needed a bit of fine-tuning for times when the phones were working extra hard, like during setup.
It's also worth noting that this doesn't just apply to phones. Any device that's especially thin or small has a chance of overheating when it's working "too hard." Older devices were thicker and often built using plastic, which made for better heat dissipation, and we just didn't see the issue as often as we do today.
What can I do?
The way to "fix" things is easy and hard: let it cool for a while.
Go through the set-up process on your new phone and set it down until it's finished. Once everything is done, reboot it. Resist the temptation to pick up your new gadget and mess with everything until it's finished doing the hardest thing it will ever do, and everything will be fine.
You might hear silly suggestions like putting it in the refrigerator or on top of the air conditioner vent, and you should ignore them. You should also ignore people telling you that your phone is defective or that you should have bought a different model. If there continue to be thermal problems, the device could be faulty, or the company that made it will need to provide a software patch, but heating up on day one is, unfortunately, normal unless you use one with a fan built into it.
