Install Messagr.

The file, what it weighs, and what to do with the link somebody sent you.

Android

No file is offered at the moment. This page will carry one again, with its weight, its date and its fingerprint, the day there is one.

The account is created the moment you open the link, not before. The application on its own creates nothing.

Open the link somebody sent you again. Messagr opens, and the account is created at that moment.
If the link opens a browser instead of the application, that is expected for an install from outside a store: your phone has not verified that Messagr can open these addresses.

Messagr for iPhone is in progress. There is no address to give you yet.

Your message reaches a person, not a form.