Reader SDK is not supported for merchants located in your country

At our local charity, we are collecting donations using the SQUARE Card Reader for card payments. It is like selling a product. We enter the amount, click on charge and donor taps their card.
I want this process simplified. I am interested in developing an android app that I will let run constantly on a small tablet.
The app will display six fixed amounts.
The donor will select an amount. He will click DONATE. He taps his card. The process ends and the system is ready for the next donor. I want do this without any further interaction.
I am in the UK and the system must be compatible with the UK security settings etc.

When creating an app, the reader sdk is giving me this message, “Reader SDK is not supported for merchants located in your country”.

is there anyway I can do this in UK?