The visual viewport API gives you details on how the user zooms and scrolls around your page.
A round up of the deprecations and removals in Chrome 61 to help you plan. In this version, more restrictions on insecure origins and a change to the shadow-piercing descendant combinator.
navigator.storage.estimate() gives you insight into your web app's storage constraints.
Background video track optimizations and automatic video fullscreen when device is rotated are here!
In Chrome, there are updates to the Payment Request API following the spec changes. Learn what they are and make changes to your own implementation.
Image Capture is an API to control camera settings and take photos.