Long before newfangled features like Remote Play or SmartGlass, Sony was fiddling with the notion of a supplemental screen to enhance your games. In 1999 that came in the form of PocketStation, a peripheral that looked like a cross between a PS1 memory card and a Tamagotchi. Sony Japan has now announced the return of PocketStation, with a Vita app that emulates it.
The trailer (via Kotaku) shows off some of the PlayStation 1 games that use the PocketStation functionality, like Final Fantasy and Mega Man. The app is free for PlayStation Plus subscribers in Japan, presumably letting them use it with their PS1 Classics purchases.
The original PocketStation never released outside Japan, which Sony chalked up to having trouble meeting demand in one country, much less several. Apps don't get supply constrainted, so maybe there's hope for it coming to America after all. No announcement of a US version has been made, however.