Google warned webmasters that it will take action agains sneak mobile redirects. Most people we see don’t even know this is happening on their website. In a nutshell, when you visit yourwebsitedomain.com on a desktop computer and a mobile device the domain should still be yourwebsitedomain.com. There are a lot of services out there that offer to create a mobile version of your website. The problem is when they use a redirect on a mobile device and your domain url is now yourwebsite.webpromo.com. Your logo and colors might be there for sure, but the content will be a little different. If you come up in Google search, then Google wants you to display the results on all devices.
We see this most often with service industries like auto machanics, and contractors. They want there site to look good on mobile, and hire a company to make a mobile version. Many times the web company links to some generic template on their domain name. It works for the most part. Your logo is there with your phone number, but the content is different from your live website.
To detect if your site is doing any sneaky mobile redirects, Google says to check if you are redirected when you navigate to your site on your smartphone. If you detect sneaky redirects on your site, Google advises you to make sure your site isn’t hacked. There could be malicious code embeded in your website files.