The latest release of Chrome Beta doesn't include many big, user-facing changes, but is instead mostly filled with incremental improvements to long-term development goals. The one goodie for end users that you may notice in normal use is the newly-added ability for websites to give you an Android notification with play and pause buttons to control audio.

For websites using up-to-date APIs, audio and video that is over 5 seconds long will result in a notification being displayed for easier control. I think of this somewhat similarly to the desktop version's indicator for noisy tabs.

Here's another look, in GIF form, thanks to Google Developers.

UPDATE: 2015/08/04 7:54am PDT BY

Media playback notifications don't use service workers.

A Googler reached out to clarify that these controls work without the use of service workers, appearing when the browser detects audio or video content that is longer than 5 seconds within <audio> or <video> tags.

This feature utilizes service workers, which were introduced in v40 and help make web apps work better offline and act more like full-fledged applications rather than mere webpages. v45 introduces several other minor improvements to service workers that are oriented towards web developers rather than user-facing changes.

Other subtler enhancements include adoption of some changes to Chrome's Javascript engine in line with new standards adopted by all browsers.

The Android version of Chrome Beta v45 should be rolling out any day now. Keep an eye on APK Mirror for the release if you're impatient.

Source: Chromium Blog