as you know Kudos is basically a way of saying Thank You, or simply a Like to a great post.
If you see a great post on Giffgaff and you agree with the content, tap the Kudos button.
It all counts towards the Payback system too.
You may find this guide offers more information regarding Kudos, so maybe take a look at that
The Essential Guide To Kudos
i hope this is helpful to all who read this thread