Following a surprising teaser last week, Square Enix has announced that a smartphone version of Valkyrie Profile: Lenneth will release this spring in Japan for iOS and Android. The official website has opened here, and it's worth noting that the game is a paid app, not free-to-play.
Square Enix states that the goal is "making it playable leisurely on mobile to many people while keeping the good aspects of the original product". Also on the site is a short video introducing the game's primary character, Lenneth, as well as some new artwork.
There's no word of a localization or other port for Valkyrie Profile at this time, so keep your fingers crossed if you want to see this in other languages on other platforms.