How do people test mobile data for mobile apps?

I was wondering how people typically test mobile data for mobile apps. We currently only test on WiFi and that has caused problems in production. Are there services that allow us to use all of our test devices on a mobile data network? Or can we really only buy a sim card for every test device? I just think that's rather clunky, especially since we only need data and not texting or calling. Or should WiFi be sufficient?

Any ideas or thoughts are welcome.

Thanks in advance!