#737 – Touch Behavior when Maximum Number of Touch Points Reached

When you already have the maximum number of touch points engaged as input devices, additional touches on the device will be ignored.

For example, assume that your hardware supports a maximum of two touch points and you’re already touching the screen with two fingers.  If you place a third finger on the screen, you will not get a TouchDown for that third finger.  However, if you leave all three fingers on the screen and then lift a finger up, the first finger lifted up will not see a TouchUp event.  The behavior can be summarized as:

• If you’ve already reached maximum number of touch points, adding fingers will not result in TouchDown events
• If you currently have more fingers touching the screen than the maximum number of touch points, lifting  a finger will not result in a TouchUp event until you’re back down to the maximum number of touch points