The Google App's version 5.10 update rolled out to the beta channel yesterday with a new waiting animation, but one change that was lurking behind is the option to open links from search results and Now cards in Chrome Custom Tabs instead of redirecting to the full Chrome browser (or your other default browser).

The option was first discovered by Cody in the APK teardown of version 5.5, but it appears to have just been activated now in the app. But, as with all things Google, there are a few asterisks attached to when it does and doesn't work. I have a Nexus 5X (Marshmallow 6.0.1) and an LG G4 (Lollipop 5.1), both running the Google App 5.10.23 and an old version of Play Services 8.4.89. Both open links in Chrome, but on the Nexus 5X, the Google App's settings shows an Open web pages in app toggle that says it's unavailable. The toggle isn't even visible on the G4. Updating to Play Services v8.7.02 activated the option on both devices (see screenshot above), so it looks like you need the newest version of Play Services to see this in action.

As to benefits of using Chrome Custom Tabs instead of Chrome, these tabs are lighter and faster, while still using Chrome's security and autofill features. So they might be better to use overall than waiting for the full Chrome browser to load and open your page.

You can grab the appropriate version of the Google App 5.10.23 and Google Play Services 8.7.02 for your device from APK Mirror and try it out for yourself.