1) Can such simple popular games be copyrighted ? Can ludo, tetris be copy righted ? If yes, where can I verify that (for. eg we can verify patents online). 2) The company manufactures booth games. Can it also claim a copyright on the online version of it ? 3) Will small modifications in the game make it escape the claim. For example http://itunes.apple.com/in/app/top-stacker/id388862228?mt=8 is a little different.
Please help me understand my various options. Should I simply take it down, ask for the proof of copyright or let them sue me ?