This will install the TAM Application, the TAM application is a 'Progressive Web Application (app)' which is a very light weight application as it uses the web browser, rather than installing third party frameworks. Its size is measured in Ks not megabytes. Future versions will be installed via 'app store' or 'play store'.
Progressive Web Applications have 2 parts:
Install a 'Service worker and cache', this allows the app to run off line.
The second is a manifest, that allows the app to be installed on the mobile's or tablet's home screen.
It also turns off all the browsers navigation bars and allows the app to behave like a native application, plus defines the app's start page/entry point.
For some android devices and desktops the add to home screen button can be used, please note this does not work in every version of the systems out there or on iPhones.
Otherwise the application has to be added to the desktop manually, see below.
As usual Apple do it slightly differently, the application has to be installed on the home page manually.