These instructions stay in the i menu at the top of the screen after you switch on, along with what changed in each release and where the numbers come from.
It is a glass cockpit panel for a phone or tablet — the instruments an airliner shows its pilots, driven by your device's own sensors and by live aviation data. It is a toy for people who love aeroplanes.
There are three ways people use it:
It is not a simulator, it is not certified for anything, and it is never for navigation.
Clamp it somewhere, press Level the horizon on the PFD, and open RADAR to see what is flying near you.
It then opens full screen with no browser bars, and works with no signal — the instruments that run on the device's own sensors need nothing from the network.
iPhone or iPad: the Share button, then Add to Home Screen.
Android: the browser's menu, then Install app or Add to Home screen.