On Saturday, September 29th, 2012, the Pokémon Centers will be adding 3 new iPhone4/4S compatible cases to their inventory. One features Lizardon, another features Muggyo, and the final one features a mixture of different Pokémon. Each case will sell for 1680 yen.
Source:
http://www.pokemon.co.jp/info/2012/09/120921_p04.html