King on steroids - Illegal move in Android mobile app

[Event "Ordinateur"]
[Site " Chess.com"]
[Date "12 mars 2018"]
[White "lanceshi"]
[Black "Ordi"]
[Result "*"]
[SetUp "1"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. e4 e6 2. e5 h5 3. c4 d5 4. cxd5 exd5 5. d4 Bf5 6. Be2 Bb4+ 7. Bd2 Bxd2+ 8. Qxd2 Ne7 9. Bf3 Nd7 10. Nc3 Nb6 11. Nge2 f6 12. O-O-O fxe5 13. dxe5 Rh6 14. h3 c6 15. g4 Bg6 16. Nf4 h4 17. Ne6 Rh8 18. Nxd8 Kg8  *

Computer stops midway through castling. On my phone the king moves 2(!) squares to g8 but the rook (which had already moved but came backup to h8 thus castling is illegal) stays on h8. Play continues "normally" After the that using the black king on g8 and rook on h8.

I have read of some illegal pawn moves when playing against the computer but that is the first time I have seen that.

You probably should open a ticket. In the app, click Settings > Report a Problem and send an email to support explaining the problem.

Also, the site only allows one account per member.

https://support.chess.com/customer/en/portal/articles/1444776-can-i-have-multiple-accounts-

I just had the same problem, also on Android, but on the Queen's side.  And the Queen's Rook had already moved.

1. d4 d5 2. e3 Nf6 3. Bd3 Nc6 4. f4 Bg4 5. Nf3 e6 6. O-O Bxf3 7. Rxf3 a6 8. Qe2 Bd6 9. Rh3 h6 10. c3 Rc8 11. Bd2 Ra8 12. Be1 Qd7 13. Bh4 Kc8