[tmurray]

I wonder how much of this is hardware versus software. Keep in mind that end-to-end latency has a number of possible sources:

- touch digitizer - CPU to do something with the input - GPU to start rendering the result - display to show the change

In particular, I worry about the first and the last. Apple can get away with using extremely high cost parts in the iPad due to vertical integration (look at the physical size of A5X, for example), whereas Android vendors generally can't. Considering that CPU and GPU are generally selling points whereas touch digitizer performance and display response time are not, it would be tempting for a margin-sensitive OEM to cut corners on those two things.

There is plenty of precedent for this: look at the grey-to-grey response time of the original Xoom.

[bsphil]

I always assumed that it was the level of abstraction required for Android to be able to function on a wide variety of hardware. iOS on the other hand is running on a relatively tiny number of devices with hardware chosen for use by themselves.

Even with a difference in milliseconds you'd still be able to discern between "smooth" and "not smooth".