Low volume mixed signal electronics production (hardware test, calibration, flashing) automation
many free ARM programmers (ST-LINK utility, Jlink etc) have  the automatic mode. I usually use ST-LINK utility + pogo pins. When the device is connected ST-LINK utility detects it, programs the flashes, sets the option bits (memory protection for example) and asks for the device disconnection - then waits for another one. Even doing it manually you can program 100-200 devices / hour.

Calibration is more difficult as you need to have


Calibration utilities in your software - often with the signalling on the pin when the calibration is ready. 
Software on the PC side - usually I write my own programs for it. So it sets the calibration data and waits for the confirmation from the device, sets anothewr ones and so on. The signaling pin does not have to be dedicated - you just need it during the calibration. Only pad for the pogo pin is needed.