Aiming to increase the buffering capacity of too tiny batteries such as the ones incorporated is some ac/dc usb devices (e.g. Luxos U, e-werk usb, etc.) I’m testing the below arrangement.
With a standard e-werk set at 4.9V I repeatedly varied the speed from 10 km/h to 20 km/h alternating in-the-between frequent and prolonged stops (0 km / h) ..
With the GPS switched-on and set at 50% backlight everything seems to work perfectly.

Any comment ??