AirPOS is fully integrated with SumUp to take card payments on the POS. You'll need a SumUp account which you can create via the following links:
Integrate your credit card payments providers with AirPOS
If you should need to refund a sale that was made using iZettle this can be done entirely within the AirPOS application if you are refunding the entire transaction. The process is fully integrated with AirPOS. Currently you cannot partially refund using Zettle, you can only refund entire sales.
How to Refund SumUp Transactions on the POS
If you are new to Zettle, or had previously used Zettle with your POS and have updated your POS app to version 3.8.18 or higher, you will be not signed in to your Zettle account and will be required to carry out these steps to get logged in
The iZettle Card Reader 2 now connects to your tablet via Low Energy Bluetooth and doesn't need to be paired with your tablet in the same way as before.