None of the officer from embassy is tracking the applicant in every minutes.

Also there’s no rule to be in one place.

But the applicant must be inside Vietnam country during the visa processing. Not leaving the country until approved or rejected.

Expect one possible request from embassy; is to take picture of where you are located. They might check where the applicant is. That is real request and also depends.

One of my friend’s friend applied in HanNoi and a few day later came to HCM to visit. Unfortunately he got rejected. I don’t think because of that likely to be coz of documentation.