Phone Chargers
When will someone invent the self-charging phone? While chargers with cords are slowly on their way out thanks to the introduction of charging pads, eventually someone will create a phone with the ability to recharge itself. Maybe via solar powers? Maybe Bluetooth?
Drivers License
While finally earning that coveted piece of plastic was the most exciting thing a 16-year-old could do, it's likely that licenses will be handed out digitally in the future. That would save teens from inevitably misplacing them. And that would also make DMVs obsolete, and nobody's necessarily complaining about that.