If the POS App freezes or shows "Shop is incompatible", a few simple steps often help. "Shop is incompatible" is a general message: It appears when a request already fails on your device, not necessarily because of your shop.
First aid
Fully restart your iPad.
Close the POS App completely and open it again.
Check whether your iPad has enough free storage.
Upload device logs before you reinstall the app
Attention: Do not delete the app before you have uploaded the device logs. Otherwise, the logs will be lost.
If the first aid steps do not help, upload the device logs so that our support team can trace the error. To do so, select Hilfe und Support (Help and Support) → Gerätelogs hochladen (Upload device logs) in the app menu at the top left. If you are not logged in, start the demo mode first via the gear icon at the top right. Then contact support and tell them the date and time of the error. Learn more in How can I send an error report from the apps?
The on-screen keyboard does not appear
If the on-screen keyboard no longer appears, first perform a cash register closing. Then reinstall the POS App and set it up again. Afterwards, test without a physical keyboard connected.
Error after installing a plugin
If the error only occurs since you installed a third-party plugin, deactivate this plugin as a test in your Shopware Admin and check whether the error still occurs.