Instashot is an iOS tool to help you access text from any image instantly.
It looks like they're using an OCR API such as MSFT's or Google's. I've tried using them in the past, unfortunately these apis are the not useful for a limited set of specific tasks. They rarely worked for more general tasks of the form "take image taken from phone, convert to text" at least not accurately especially from handwritten text
Works nicely for digitallog generated text
Doesn't work for more general purpose tasks like converting handwriting