The Preferences screen is opened by clicking on
Preferences from the right menu.
From this screen you can set General and Notification preferences.
In the general section you can make changes to the time format, toggling between 12 and 24 hour format.
By default the 12 hour format is set, to change this click on the toggle button.
In the notifications section you can chose whether to receive challenge notifications or not by clicking on the appropriate radio button.
To update your preferences click on the