Core Graphics drawing lags on iPod 4th generation and above, but smooth on 3rd gen iPod touch?

Question

Ive developed a simple drawing app using core graphics to draw with your finger on the screen using Core graphics.

On 3rd generation iPod touch's it runs very very smooth, but anything better or more recent it lags like crazy, even on the new iPhone 5!

Can anyone explain?

Answer 1

Sounds like it might be related to the retina display. You can try using CGContextSetInterpolationQuality to speed it up a bit, or even change the content scale factor to something lower. If that doesn't help its probably the input logic/timing.