I have never actually licked my phone or any other gadget that I own (I love them, but there is a line. Tongue love crosses it), but scientists are developing technology that would utilize your tongue to control computers and home gadgets.
The technology, called the Tongue Drive System, is being made primarily for patients with disabilities, and the concept involves using your tongue as "a joystick" to control wheelchairs, home appliances, and computers.
This is especially beneficial for those who are paralyzed from the waist down, since the tongue is controlled by the brain and not affected by the spinal cord. Technology: licking another problem!