Unless you have a backpack strapped to your back 24/7, carrying around a back-up charge for your phone is pretty inconvenient. It’s not like you want a power pack in your back pocket all day. For a quick jolt that isn’t a pain to bring with you, get the Power Pen. The world’s first pen with an integrated smartphone battery can be dropped right in your shirt pocket for impromptu note-taking and phone resuscitation. It includes both a lightning connector and a microUSB so you can charge your iPhone or Android device. It even has a stylus so you can write something on your freshly charged smartphone after you juice it.