Google Smartphone User Agent Changes Names

Google's smartphone user-agent will be updated April 18th, 2016 so that the renderer is compatible with newer web technologies. In their announcement, Google says that the change shouldn't affect 99% of existing sites. Ones that may experience a problem are those that look for a specific Googlebot user-agent string (a practice that is not recommended as it's considered a form of cloaking). If you're unsure if this is the case on your own site, you are encouraged to run it through the Fetch and Render tool that's already been updated with the new user-agent.

The smartphone user-agent will be changing from this:

To this

You can read Google's announcement on the change here and post questions to the Webmaster forums here.