Google is retiring a version of Googlebot that was specifically designed for crawling content on feature-phones. Feature-phones are limited mobile devices, essentially the predecessors of smartphones, and they require their own form of markup for web content.
Since feature-phones are not as widely used as they once were, the majority of websites do not provide feature-phone-compatible content in WAP/WML. As a result, Google will no longer be using the feature-phone Googlebot.
With the feature-phone Googlebot no longer in operation, its Search Console tools have been rendered obsolete. These include the Fetch as Google feature-phone options and the feature-phone crawl errors report.
Google says these changes should have minimal impact on webmasters, as most sites don’t serve feature-phone content anyway.
If your site has been serving feature-phone content, Google recommends using a different type of markup to direct feature-phone users to content that’s properly optimized for their device:
<link rel="alternate" media="handheld" href="[current page URL]"/>Rest assured, none of these changes affect smartphones; they only impact the crawling and serving of content on feature-phones.
