VKontakte: how to find out if a user has deleted an iFrame application?

Question

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The VKontakte application is a bundle of two: iFrame (interface) and Site (with offline access).
With a Site type application, everything is simpler - there is a user access_token that can be checked with account.getAppPermissions .
How, without having an online user at hand, with fresh tokens from iframe, check that the iframe application is still installed?
Those. given: user_id, app_id, app_secret. I need to know if he still has this application installed? He gave only basic rights - to access his information.

Answer 1

It is enough to get a token for your user and use it to bypass everyone through users.isAppUser . This is if the application id is the same. Otherwise, you need to connect the iframe application as a website and make a token for yourself.