In the "better than Tesseract" category is also Microsoft Azure OCR (not as good as Google) and the OCR.space OCR API (also not as good as Google, but 100* times cheaper/free, and supports PDF).
The best - and most expensive - solution is still Abbyy OCR. They provide an SDK than can be used locally.
A new local OCR solution is Anyline.io, but I have not used them yet.