The conversion relies on some kind of cloud service (possibly Google's Cloud Vision API). So you need to be connected and there are privacy/security implications. And, it's very dependent on your handwriting. I cannot get coherent results with that feature, but my handwriting is as readable as base64-encoded Perl. I've seen it produce impressively good results when other people try it.

The process itself is indeed smooth, select an item in the menu and a few seconds later you have the text, which can then be emailed.