We may receive a commission on purchases made from links. For those who have ever been in public with a dead smartphone, you likely know the importance of having access to power. Whether you just want to play a mobile game to pass the time or you plan to use your device to call for a ride, having dead batteries can lead to precarious situations. While we can recommend plenty of cheap power banks users swear by , Amazon currently has one on sale that's small but mighty. Available on Amazon with a sizable discount, the Rorry 5000mAh Portable Charger Power Bank is small enough for your keychain or an everyday carry bag. With a slim, portable design and a max output of 5V, it's got some surprising features, including the ability to share it with someone else while you're charging your own device.…