The Lexar JumpDrive M20i - like the SanDisk iXpand - provides a straightforward way of getting files on and off a late-model iPad or iPhone.

Equipped with USB 3.0 and Lightning ports featuring a convenient two-way slide action, you can use it as auxiliary storage for the iPad, whether that's to carry an extra-large collection of videos and other media while travelling, or for easy backup when away from a computer or in the absence of connectivity.

Lexar's JumpDrive app can automatically backup contacts and photos from the device to the M20i, and connects to Dropbox, YouTube and Vimeo accounts.

So when using the app to look at videos, for example, you can see content stored on the JumpDrive, in the Camera Roll, on YouTube and Vimeo, and in other locations. A useful aspect of the app is that it can play some video formats not natively supported by iOS, including AVI, FLV and WMV.

Dropbox integration makes it easy to download files to the M20i, or to upload them from the iPad/iPhone or M20i to Dropbox. While this to some extent duplicates functions in Dropbox's own app, this feature made sense to us as it saves unnecessary clutter in the device's internal storage.

The JumpDrive app is able to display Word and Excel files, and if you need to edit them it is a straightforward task to send them to a compatible app such as Pages or Excel.

The app also incorporates a voice recorder. Files are automatically saved in the in-app storage area, but can be moved to the M20i or to Dropbox or other storage services.

Disappointingly, several functions require in-app purchases for activation. So while you can conveniently stream YouTube videos via the app, you can't cache them for offline playback without an add-on. Individual in-app purchases are needed for calendar backup, Facebook album backup, Flickr album backup, support for zip files, and integration with Google Drive, Instagram, Tumblr, or Vimeo. Consequently we did not test any of these extras.

When it's time to move files between a computer and the M20i, it just plugs into a USB port and behaves like any other thumb drive with the extra benefit of USB 3.0 speed. Lexar claims read speeds up to 95MBps and write speeds up to 20MBps with USB 3.0.

So how does it compare with the iXpand? The M20i is almost half the size and is noticeably lighter, and its slider design means there's no cap to lose. On the other hand, the iXpand's Lightning connector is on a short, rubbery arm that we think provides a degree of protection against mechanical damage when plugged into an iPad or iPhone. How careful are you with your equipment?

The JumpDrive software has a more contemporary look and feel than the SanDisk app, but it doesn't provide encryption, which can be an important issue for mobile devices and storage.

The JumpDrive M20i comes in three models: 16GB ($72), 32GB ($103) and 64GB ($165), compared with $79, $99 and $148 for the equivalent iXpand variants (despite the adverse shift in the exchange rate, that's somewhat cheaper than when we tested it back in February).

These are fairly serious prices - with good reason - compared with conventional thumb drives, so being asked to pay to unlock various software features seems inappropriate. If Lexar dropped the in-app purchases and added encryption, it would be the clear winner.