iOS 10, released to the general public this Tuesday, changes the way you interact with the home button to unlock a device. Previously, if you have Touch ID set up, you would touch your thumb or finger on the home button to unlock an iPhone or iPad. Now, the iOS device asks you to “Press home to unlock.”
Fortunately, you can change this, and go back to the previous, simpler method of unlocking the device, though you may prefer having to actually press the button. I suspect this change is because of the way the home button works on the iPhone 7, which doesn’t have a physical button that presses.
To change this behavior, go to Settings > General > Accessibility > Home Button, and toggle Rest Finger to Open. Note that this only works on devices with the second generation home button or later; that’s the iPhone 6, iPhone SE, iPad Pro, and later.
h/t Rob Griffiths.