There are lots of ways to transfer files between your an Android device, but the simplest method has been to tether one to your using a cable. SanDisk has a better idea: Its Ultra Dual B Drive can be used with Android smartphones tablets with s. 

The thumb drive has a stard Type A B 2.0 plug on one side, a Micro-B B 2.0 plug on the other. I tested the 32GB model with an HTC One smartphone. Both of the drive’s connectors are protected by a sliding plastic shell that automatically retracts when you push the plug into a B port (you’ll need to pull the covers back out when you unplug it).

Due to the thickness of the thumb drive’s shroud, I had to pop the bottom of my phone out of its Speck case. But I’ve encountered the same issue with right-angled headphone plugs, so this isn’t a showstopper by any means.

Having both connectors makes it extremely easy to transfer files between your Android smartphone or tablet your . Move or copy files from your phone to the storage device, unplug it, plug it into your , move or copy those files to that device ( vice versa). If you use a cloud-storage service, you can copy files to from there as well. The storage device measures just 1.5 inches long 0.75 inches wide. It has a lanyard ring so you can add a tether, but the hole is extremely small.

The HTC One doesn’t have its own file-manager software, although there are a number of free Android apps available in the ay store. I’ve been using ES File Manager for a while, but I’ve since switched to SanDisk’s free Memory Zone, which has a much more polished user interface. Rather than having to drill down into the phone’s directory structure, Memory Zone indexes sorts all the files it finds on the phone on any storage device that’s plugged into it. You can add any cloud-storage services you use—such as Dropbox— the app will index all the files stored there as well.

Once the files have been indexed, you can press the music icon to see a list of all the music files in storage. ess the lscape icon you get a list of all the photos. There are also icons for movies, documents, apps. Tap the file, a Complete Action Using pop-up menu appears. If it’s a music or video file, you can play it with whatever media player apps are installed on the device. If it’s a photo, you can view it using your favorite photo editor, so on.

ess hold a file name, a pop-up menu will appear giving you the option to copy the file to another storage device or to your cloud account. You can also rename or delete the file, make the file private (these are password protected), or share the file on Facebook. Memory Zone also has a backup/restore function that you can set to automatically back up all or selected files from your phone to a B storage device or—more practically—to your cloud-storage service.

This element of the app informs you of the backup’s progress, how fast files are being transferred, an estimated time of completion. Backups can be performed over a 4G connection or limited to using -Fi, so they don’t suck up your cellular data quota.

SanDisk’s Ultra Dual B Drive would be a lot faster if it were outfitted with a B 3.0 interface, but that would also make it more expensive. It’s already a bit pricey, with the 32GB model selling for $30. That’s a $10 premium over a conventional 32GB B thumb drive, you can buy a 10-foot micro B cable for as little as a buck a half. (SanDisk also offers 16GB Dual B drives for $20, 64GB drives for $50). But a cable isn’t nearly as convenient.

SanDisk isn’t the first company to hit on the idea of a two-headed storage device. Sony announced its own line of two-in-one drives last December. But Sony’s models top out at 32GB, the company doesn’t offer an Android file manager.

os 

• Has both Type A Micro-B B plugs 
• Very small 
• Great file manager 

Cons 

• Speed-limited B 2.0 interface 
• Tiny lanyard hole 
• You might need to remove your phone’s case 

Score: 3.5 stars