How closely can a game resemble another game without legal problems
I want make a game similar to Pocket Tanks but for Android and then sell it. Since I am not directly copying anything from Pocket Tanks, but simply using it to give me ideas, I should be allowed to make it. I don't want to finish making my game and then get into some legal trouble, so I wanted to ask here if its allowed. If this is the wrong place to ask, can you tell me where I could ask this question?