Hi there, JanK13.
Can you please provide additional information on what product of QuickBooks are you using? I'd appreciate any further details you so I can provide accurate details.
Every QuickBooks needs parts that help you run your business faster and easier. To make sure your QuickBooks system runs smoothly, you'll need to use a compatible card reader that you can use on your new Android phone.
I attached a screenshot below to see a list of agreeable card readers.

For additional information, you can click this article: What devices are compatible with QuickBooks Point of Sale?.
Feel free to post again anytime you need help with QuickBooks. I’m always here to help. Thanks for dropping by and take care!