How can I make tesseract on iOS faster?

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 a Video Stream.

I am using tesseract 3.01 with a custom training file for my font.

Here is what I do:

Setting up tesseract only to find numbers (0-9)

1. Shrink, Deskew and Binarize Image
2. use GetLines to find the line I want the text of
3. setRectangle to only recognize the line i want
4. getUTF8Text to get my text <- this alone takes 2-3 seconds

Are there any suggestions to speed up the process?