We went hands-on with Mazzo’s PowerDrive Slim, which combines an external battery with a hard drive, to give you extra storage and extra battery life for your iPhone. There’s 32GB of storage space for storing files, photos, and videos, plus a 3,000 mAh battery that translates to approximately one full charge for an iPhone 6 Plus.
Files can be transferred to the PowerDrive Slim using the accompanying PowerDrive iOS app, and at the same time, it can charge your iPhone. You’ll need to supply a Lightning cable for transferring files and for charging your iPhone from the PowerDrive Slim.
Size wise, the PowerDrive Slim is thicker than an iPhone 6 Plus, but not quite as wide or tall, so it fits easily enough in a pocket. We liked the portability, and we were impressed with the app, especially when it came to the auto backup feature for photos.