I am going to use a motor with gears powered by a fidget spinner or crank that you hand power. Everything would be glued onto a piece of wood which you would carry around. The wires would be attached to the motor, 5v regulator and female USB port.
I am planning on making a portable mechanically charged charger for my phone. It will not necessarily use a hand crank but It will have some form of device to transfer mechanical or kinetic energy into electrical energy. It will have a USB port in order to fit with all phones but the wire connecting it would be separate. This would be convenient always and would always work but it would take a while of cranking it before you get significant charge. So it would only be useful when you have a lot of free time and don’t have any other options to charge with.