Try to select a deck that has strong cards on all four edges. If you're playing first, it's often best to lay down a weak card so you can recapture it in a later move. As it comes to the final couple of moves, if you're winning you need to think ahead in terms of whether your opponent can do any Adding or Mirroring moves and try to block them. The elemental boost and debuff positions on some grids can be important in terms of the way they either increase card numbers by +2, -1, or -2. This can have a big effect in terms of Mirroring, so it's often best to lay cards down on them early so you aren't surprised later. You can log into your account using either the iPad's Arena 9 HD app or the iPhone's Arena 9 app as it's shared using your OpenFeint details.