It looks like an iPod Nano. It's as small as an iPod Nano. It's certainly as light as an iPod Nano. But it's not something that's made by Apple. It's actually the Sony Ericsson (SE) LiveView and it sure packs a mean punch considering its tiny size.
The LiveView is a smartphone accessory that connects to your phone via Bluetooth. It essentially functions as a remote control so you can perform some basic functions without having to fish your phone out of your bag or take it out of your pocket.
On the LiveView, you can read your messages, see incoming calls, view the latest Facebook and Twitter updates from your contacts, and check your calendar. The screen has a resolution of 128x128 pixels and features a 1.3" OLED color display. It is compatible with Sony Ericsson's Xperia X10 series as well as with other brands of mobile phones that run on Android 2.0 and above.
You can remotely toggle your music player with LiveView and read RSS feeds while you're at it. It can also be used to sound an alarm on your phone if you're having some trouble finding it. A great feature of the LiveView are the plug-ins that you can install from third-party developers which can easily be downloaded straight from the Android Market.
You would probably expect the LiveView to sport a touchscreen, but unfortunately, it doesn't. You have to make use of the four-way touch-sensitive controls on the black border in order to navigate through the device.
The LiveView is especially useful for people who are always on the go. It can be clipped on to virtually anything: on your belt, on your binder, on the sling of your bag, on your planner, and even on your watch. It's also pretty convenient to just check the LiveView instead of bringing out your phone when you're someplace crowded or when you want to check your calls or messages in a more discreet manner.
Sony Ericsson released a software update in early 2011 to address some bugs and to improve the LiveView's overall functionality. The update was also able to improve its compatibility with other non-SE Android devices.
Source: Sony Ericsson