Fastmail has a native Android app:

https://play.google.com/store/apps/details?id=com.fastmail.a...

Which is basically just a webview. Don't get me wrong - it's a good webview. But as a consequence there's no offline functionality at all - not even to view emails you've just opened a minute ago. Otherwise I think the Fastmail product is great.

... that is just a webview.

Really curious in what world that can be considered native.

Oh I thought you were saying they only had a web app, and you didn't realize they had an actual app.

I use the Fastmail Android app and didn't realize it's just a webview.