Passing the Google mobile friendly test with WPTouch and WPEngine

Preparing for Google’s Mobile Friendly update on April 21st, we noticed that some of our clients’ sites using the WPTouch plugin were unexpectedly failing Google’s mobile-friendly test.  Since all of the sites were hosted with WPEngine, we contacted both WPTouch and WPEngine support. After a bit of back and forth, WPEngine solved the problem by adding the following to the varnish cache for the affected sites.

set $mobile_bot 'no';
if ($http_user_agent ~* (iPhone) ) {
	set $mobile_bot "X";
}
if ($http_user_agent ~* (Googlebot) ) {
	set $mobile_bot "${mobile_bot}Y";
}
if ($mobile_bot = "XY"){
	set $is_bot 0;
}

If you’re having a similar problem passing the mobile friendly test and use WPTouch and WPEngine, try it out!