I am struggling with tesseract ocr on ios. Everything works fine but it is really slow. 2 - 3 seconds recogintion time for a single line of digits.
I am reading from
One thing you might want to try is do it in the background. It will not improve the recognition speed, but by having the user do something else it might appear faster. This, of course, depends on the use case (I have one where this is a nice improvement as it seems very fast, while I just start sooner than expected). The trick is that ios apps are about perceived performance, not actual performance (although it naturally has a big impact on perceived performance).