As children I am sure we have all played Guess Who. And, as teachers, you've probably played it with your classes.
Now, why not play it with electronic devices?
This is a great, and quick, pair work activity to get your students producing questions and descriptions about electronic devices.
Split them into pairs, give each student a sheet and have them, in secret, choose a device. The aim of the game is for the other player to guess, using questions, which electronic device has been selected. There are some example questions on the board but you might need to drill/pre-teach a few additional ones.