That all sounds right, for web at least, but most of the services that require api key, actually require from you to enter a domain to which this api key is given and for mobiles sha1 of your app at least on android. So requests from different domain and from different mobile app will fail. How this proxy makes things better, what about you will have to pay more for that proxy to work non stop for everybody. Why implementing the same authorization twice?

about which version of flutter is this article. I'm perfectly fine without multidex on 1.9.1+hotfix.6 (previous stable). The new 1.12.x is unusable for me. The project doesn't compile even after updating the firebase libs

Well, normally i put the sw at last moment. Plus you could control the duration of the cache and invalidate.

That's easy don't be angry. I'll explain tomorrow. It's late here.