How can I diagnose performance problems with OIDC in mobile web app?

I’ve got an app which uses OIDC for authentication with Siemens MyID. It all works fine, but the initial app loading performance on mobile (PWA: not native) is very slow. It takes about 15 seconds to get to the first page, whereas the desktop load is very fast. This seems to be related to the use of a trusted device, which then performs an automatic login. 15 seconds is too long, especially if the user is already logged in and the app needs to reauthenticate. I’ve tried all sorts of performance profiling tools, but don’t see where the issues are. Can anybody suggest things I can try to see where the bottlenecks are? If I could at least display something while this is happening, then users would know it is working and they should wait
1 answers

Hi Colin,

I'm more familiar with native then PWA, but in native long loading times or 'hanging' splash screens are due to syncrhonizing large datasets for offline use. 

I also saw an option about preloading static resources in Progressive Web App | Mendix Documentation, which might be a cause for longer initial loading times?