According to Official Guinness Records,
The most playable pixel art characters in a mobile game is 627, appearing in Brave Frontier, published by Alim Co., Ltd. (Japan), Shinjuku, Tokyo, Japan. The record is based on market research carried out by VLC Co., Ltd, verified on 31 October 2017.Brave Frontier is a role-playing mobile game which was initially released in 2013 on iOS.
For a complete list of 2017 records, please visit 2017 Guinness Records in Japan.