Level-5 announced the release during the Level-5 Vision 2016 event in Japan the next Layton game the Lady Layton for Nintendo 3DS. The new title will be available from 2017 Spring in Japan but a port version also release on iOS and Android.
In the game you play with Professor Layton’s daughter and the game style will be the same as the original Layton 3DS games. Level-5 going to publish more details about the game in the near future. Stay tuned!