Dashboards not working on iPhone or Android

I’ve an interesting one. I can access my Ubidots account absolutely perfectly from a browser.

I have both an iPhone and an Android. Weirdly, neither will show up my dashboard.
I just get the ubidots logo going round and round when I try and access a dashboard.

This is new - in the last week or so.

Any ideas? I’ve emptied the cache and reinstalled on both devices.