slow loading

I am using the cronometer app on both my ipad air and my samsung s9. I have the most up-to-date OS for both devices, and the app is updated to the most recent version.

I am experiencing very slow load times on both devices on all pages. I am not having this difficulty with other apps, and I have tried this on several different wifis.

I'm wondering if there is some kind of data stored on my device that could be cleared that might help the load time? I have been using the app for several months, and I imagine there is lots of data stored.

Thank you.