The "subscribe" button in the VK application - how to implement it?

Question

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The task stuck: put the "Subscribe" button into the VK application.
For the desktop, nothing complicated: a new browser window opens and the subscription page already opens there.
But this did not work with the mobile application - most likely, there are simply no browser pop-ups.
How then to implement the feature?
UPD: in this case, the "application" is an iframe of a web page embedded in a VK application

Answer 1

The application is direct mobile-Standalone? Then the groups.join() API method will help you join directly (before that, request additional rights if there is no "groups" yet).
Or specify how the application works - a web component in a mobile app or just in any mob. browser?
Ps Widget "Communities" do not stick?