Smartwatches may be less cumbersome than smartphones, but those little screens of theirs can only display a limited amount of content. We've already seen efforts to move the touchscreen control surface off of the watch, but researchers from Dartmouth College are taking another approach – they've created a prototype smartwatch with two touch-sensitive screens.

Known as Doppio, the watch has one base screen that's mounted on the wrist strap, along with a removable top screen that attaches to that base screen magnetically.

In the watch's default configuration, the top screen is stacked on top of the base. In that setup, users can access one app on the top screen, then flip that screen back like the cover of a book to access a second app on the base beneath it. It's also possible to switch between apps on the top screen, simply by rotating it relative to the base.

If users wish to widen the base screen's display, they can do so simply by attaching the top screen to one side of it. The two screens know on which sides they're joined, and will adjust their displays accordingly.

"Our proof-of-concept hardware prototype demonstrates how Doppio interactions can be used for notifications, private viewing, task switching, temporary information access, application launching, application modes, input and sharing," says lead scientist Xing-Dong Yang. The prototype is demonstrated in the video below.