3 ms·

If it's obvious, why didn't it exist on any of the touchscreen products which went before the iPhone?

• pjscott 14y ago
  How many of those touchscreens could detect multiple touches at once? That's a prerequisite for doing pinch-to-zoom with a capacitive touchscreen.
• mibbitier 14y ago
  It likely existed on the first light-pen devices from the 80s. Apple just happened to popularize it.