Android
On Android, you can either mute push notifications for the time being or for a set amount of time. You can choose between turning them off fully, muting them for 2 hours, 4 hours or until 8:00am the next morning.
All you have to do is press "settings," then "push notifications," then tap the bell in the top right hand corner.
This pulls up a menu that allows you to choose how long to mute them for.
It also allows you to turn them back if you have turned them off.
iOS
On iOS, you can mute push notifications in the app for 2 hours, 4 hours or until 8:00am the next morning.
To do this, go to 'settings' then 'push notifications' and at the top of the list you will see a toggle next to 'mute' slide that over and then you choose.
If you want to unmute them, slide the toggle back and press 'unmute.'
Here is a video:
N.B. You can also hide the score of a match to mute notifications for that specific match, see this article for an explanation: https://goo.gl/rDk5kV