We spent 3 days with an Android phone that has a 10,000mAh battery and didn’t need to charge it once

Anker 622 MagGo Magnetic Battery — Not everyone can get a 10,000mAh phone, but you can bolt extra hours onto the one you already have. Anker's MagGo snaps magnetically to the back of your phone and charges wirelessly, with a fold-out kickstand for hands-free video. It's a slim way to kill battery anxiety without carrying a brick and a cable.