Some person puts servos on the leading edges and spreaders with a mini processor - to control the shape of the sail. Attach this to a remote transmitter and you fly the kite by wire. No strings attached.
You'd need at least one string, otherwise it's hardly a kite. Kites depend heavily on tension; take that away and you have a glider instead. Also an interesting device, but not a kite replacement.
I'm sure we'll see "active" frames eventually, but I don't think the tech is light/cheap enough yet.