I hv seen recently corona work closely with pubnub.
Also corona is a promising sdk which provide useful sample code.

I study pubnub codes and hope to create my next multiplayer game.
But it seems like all game winning logic are hosted under client (iphone app)
Hope all game dev gurus can provide me some input,
is it possible to crack down/ reengineer the client?
Example: default logic is to auto generate 100 credit a day for a player, end up someone abuse the game client to gain 10000 credit a Day? How to avoid such abuse for standard multiplayer game?

How can pubnub/corona resolve such cases?
Maybe someone can code a sample poker game? :)

Great question! When dealing with valuable details like money you will need to authenticate and run game rules on your own private closed network of servers. Using HTTP requests functions in Corona you will communicate with your server to perform Poker and Points/Money logic on your server. Then your server will synchronize with the clients via PUBNUB.Publish({}) functions. The Mobile Phones will be listening for sync using PUBNUB.Subscribe({...}) function.