We are in a Smartphone era. As discussed previously, the form factor of most cellphones has converged to slant. Cellphones became a slab, a rectangular box with a big flat screen. The keypads have disappeared and so have the Call and End Call Buttons.
Do you still remember the days when you could press the Call button to review the recent call list? Do you still remember the days when you could press the End Call button to terminate any tasks; held the End Call button to switch off your phone? These days were over. The physical keys have been replaced by virtual keys. The two keys sometimes even merged into one key (that toggles) on some mobile phones!
Change is sometimes good and sometimes necessary. But the change process can be very painful.
Before the disappearance of the End Call button, when you wish to terminate a conversation due to whatever reasons, all you'd have to do is to remove the phone from your ears and quickly press the End Call Button. Whether that person is a telemarketer, an angry spouse or a made-you-angry spouse, when you pressed that button, the call is over.
If the same situation happens nowadays, you'd have to remove the phone from your ears, wait for at least half a second for the proximity sensor to work its magic to turn the screen back on. No matter how rushed you are, you must refrain from touching any other keys as you might screen-locked the phone or exit the dial pad mode. Once the screen has turned back on and displayed the End Call button, you can finally locate that virtual End Call button and press it once. At the same time, the End Call button toggled and became the Call button. If you have lost your cool and pressed on the same position once more, you'd end up calling the same person again!
There are certainly other examples. Let's hope that manufacturer would come up with solutions to ease our pain in the process of change.