I walked into the T-Mobile store in Fairfax, Va., with my iPhone 6. This is the same phone I wrote about a year ago when I finally gave up my BlackBerry for an iPhone. I told the sales guy that I wanted to do a trade-in, and a few minutes later I had a new iPhone 6s.
Not that you'd be able to tell the difference. Unless you look at the back of the new iPhone where there's a letter "S" in a square, it's unlikely you'd notice that the new phone is one-one hundredth of a millimeter thicker.
You might notice that it's a half ounce heavier, although I didn't. Otherwise, my new Space Gray iPhone 6s looked just like the earlier model I'd traded in a few minutes before.
It wasn't until I got the new iPhone back to my office and had restored the settings from the old phone that I noticed the significant speed difference. After I'd set up the fingerprint scanner, I found that the old practice of briefly touching the home button to see my notifications would no longer work.
This new phone and the fingerprint reader are so fast that no matter how quickly I touched the home button, the phone's home screen would open. I now had to see notifications by flicking down the screen from the top.
Next I tried touching and holding the Maps app on the home screen. A menu popped up that would let me choose directions home, to send my location or to drop a marker where I was at the moment. For whatever reason, the Maps app thought I was in Austin, Texas, which was where I'd last used the Maps app on the previous iPhone.
The ability to press and hold the icon is an example of Apple's new 3D Touch feature, which also exists on the Apple Watch and on some MacBooks. This feature also adds new functionality to the email and message apps, so you can press an email message and get a peek at the whole message, or you can peek at a text message.
Some of Apple's built-in iPhone apps include the ability to respond to 3D Touch, but not all of them. When you press one that doesn't support 3D Touch, the screen vibrates and you feel a vibration from the phone.
I found the 3D Touch feature to be of limited usefulness in some areas, but the ability to use 3D Touch to preview email and text messages was quite useful.