The All4s App is quite simple to navigate. At the top there is a book icon. Tap it for the rules of the game if you're new to it and would like to become part of our national culture. Other than that, tapping the pack of cards on the top right or the Start Button (top left) would kick you off.
You can maually manipulate your hand by dragging cards right and left to rearrange as you would normally do in a game. To play a card, simply swipe it to the table or double-tap it. Tapping a card once highlights it and lifts it slighly above the rest.
Tapping the wheel icon at the top right of the screen transports you to the Settings page. Here you choose whether to have the game score by digits or by safety matches as is the native custom.
You can toggle the sound on and off here or do it by tapping the speaker icon in the main menu on the game page for easy access.
For each of the Card-Backs, your chosen Avatar or the game Background, you cycle through all the available choices by repeatedly tapping on the respective icons.