Starting today, Google will use yet another of its algorithms to detect if a website may not work on your device and then warn you. Should you search for a website in Google Search on your Android 4.1+ phone that may be an Adobe Flash laden page, Google will toss in a note under the search listing to explain that you may not receive the best experience should you visit it.
Of course, Google also took a moment in this announcement to explain to developers that they should probably think about adopting universally supported technology, like HTML5 in their sites going forward.
Here is an example of the warning you will see.
Via: Google Webmaster