Inter-app communication is one of the major missing pieces of the web platform, and specifically one of the last major missing features is native level sharing: Web apps need to be able to get data out of their silo and into other web sites and apps; they also need to be able to receive the data from other native apps and sites.
I think there is a silent war between Android and Chrome, and the first one seems to be ahead. PWAs on Android could have a much better experience, and it could have more supporters if the Android team could push this a little further, letting some game changer abilities get into the platform.
I love when Web site/apps work even when I’m offline. I’ve made my SVG game esviji work offline thanks to appcache just after attending Jake Archibald conference about why Application Cache is a Douchebag during the 2012 edition of the Paris Web conference. Fortunately, we have now Service Workers (in some browsers), which gives us more control over this kind of cache for offline browsing. But as Uncle Ben says, « With Great Power Comes Great Responsibility ».