Some websites and even specific content from the US are blocked here so sometimes there is an app or a Netflix show that is available in the US but not available here. I had no issue downloading the app over my home connection here but others have had trouble based on how their internet connection is routed.

Honestly, I didn't need the app for anything. It's a way to review your results, but the lab report you need comes via email anyway. And the test is done from their website not the phone app.