There's a severe flaw in the way the Call xxx (and Raise xxx) checkboxes are implemented when making your move prior to your turn. At least in the Windows client. For example I checked the "Call xxx" box when the current call was at 30 chips. A fraction of a second later the player on my immediate right raised to 105. The amount on the checkbox immediately changed to 105, left my check mark there and proceeded to call those 105 chips. Even if the raise on my right had happened a fraction of a second before I checked, it should have removed my checkmark and then either disabled the checkbox for a full second, or shifted it up or down so that my click would have landed on an empty space. The way it's currently implemented, those options are too dangerous to use.