Yamaha has launched the SHS-300 Keytar and posted a couple of videos on it. It is a 37 key instrument that can run from battery power and has USB MIDI. The instrument features 12 presets using AWM stereo sampling for sound generation and has 32 voice polyphony.
This is what Yamaha has to say...
The SHS-300 Keytar (“Key” board + Gui “tar”) features a sleek, compact design that gives you immediate access to the exhilaration of playing music, even if you've never played an instrument before. Use the free dedicated "Chord Tracker" app together with the JAM function and the sounds that match the chord progressions on your smart device will be automatically assigned to the SHS-300's keyboard, allowing you to play along with your favorite songs as if you're part of the band.
Pricing and Availability:
Recommended retail price based on Germany including 19% tax: 243€