Online games: update the clients with deltas or with the new status

Question

I'm implementing a online chess for Android and I have a question about how to update the players with the other player's movements.

For example lets imagine the Player1 moves his tower from a1 to a7.

What should I do?

• Send to the Player2: "a1 to a7" (with some kind of checksum of the full board to avoid errors)
• Send to the Player2 the full board with the up to 32 pieces

Answer 1

Support both.

• Only send deltas during events, but
• Allow the client to request full state, for any reason, through a separate API.
• Include and increment a sequence number with each event so that it is trivial for a client to detect missed updates.