This means your mobile site will under goes some changes when Google launches the update. According to the blog post title “Continuing to make the web more mobile friendly” from Google Webmaster Central Blog, Google will be rolling out an update to mobile search results in early May. The update is intended to increase the effect of the ranking signal to help users find more pages that are relevant and mobile friendly. Again, although Google says that our site won’t be affected much but no guarantee has been made. It is still up to us to check and confirm the effect of the update towards our site. If you have no idea on how to check and confirm your site, refer to the guides provided in the blog post above. There are some simple guidelines which you can refer to.
Honestly, there are no rules on how you should design and build your mobile site. Your site will have a problem with Google when only you go against their rules and condition. The best way is to test it out. Especially while Google is still working and building their search algorithm to suit mobile usage, a lot of things are still within the grey area. In other words, nothing is confirmed until Google put it into black and white. The situation is more a less the same right at the beginning when Google started to tune their search engine for laptop usage. The process is just a repeat of history.