Google has updated the user agent for the AdsBot Mobile Web Android crawler. If you hard-coded this bot for any purposes on your site, you will want to update your code.
The new user agent for AdsBot Mobile Web Android is:
Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/WXYZ Mobile Safari/537.36 (compatible; AdsBot-Google-Mobile; +http://www.google .com/mobile/adsbot.html)
the old user agent What:
Mozilla/5.0 (Linux; Android 5.0; SM-G920A) AppleWebKit (KHTML, like Gecko) Chrome Mobile Safari (compatible; AdsBot-Google-Mobile; +http://www.google.com/mobile/adsbot.html)
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Image credit to @okaylizzi