navigator.storage.estimate() gives you insight into your web app's storage constraints.
With Chrome 58, Progressive Web Apps are more immersive with display: fullscreen. IndexedDB 2.0 is now supported and sandboxed iFrames get more options. Pete LePage has all the details and how you can use these new developer features in Chrome 58.
The sw-offline-google-analytics library gives you everything you need.
Long awaited feature for Chrome, Blob support on IndexedDB landed in Chrome Dev.