Google is going to roll out the new security warnings in Gmail for Android and on Web as well. Earlier few months back Google starts blocking websites on Google chrome with the malware containing Download buttons. Now again google is trying to give users the hassle free experience in Gmail.
In this new security feature if you receive an unauthenticated message with either Sender Policy Framework (SPF) or DKIM. Then you will see the question mark in place of the profile photo, corporate logo, or avatar. This feature will work on both Web and in Android App.
Now if you receive a message with a dangerous link i.e. a link for heading to the website which haves malware and unwanted softwares. Then you will see a warning if you click on that link. However, please take a note that it is not necessary that every email or website which is affected by this feature is dangerous. But to remain secure to open these links be very careful and replying to the emails with these types of warnings.
Google says the update might be rolling out in a couple of weeks and it will take 2-3 days to reach each and every user of Gmail on Android or Web.