Hi,
Public build will be aavailable in around 2-3 weeks.
Right now dev focuses on adding more interactions, events and story to the game. He will add more characters when the time comes for them.
As for phone performance, dev is aware of various issues, yet the main platform, he was creating the game for, was PC, but due to the high number of reports coming from Android users, he has rearranged his priorities and have fixing Android build higher on the list.
For now disabling shaders and lightning in the game settings is all you can do except upgrading your phone.
Cheers