Add a tweet button – Adding a tweet button will increase the social presence of your pages and let visitors more easily share your content.
Add a Facebook share or like button – Similar to the tweet button a share button acts only in your favor when you need to popularize your content while a big amount of likes can sway new potential customers to your products or services.
Add a Google+ button – When talking about Google+ you have to differentiate that Google’s social network does not equate to your page ranking in Google. They are not directly connected but having a big following on g+ can help you with your website’s popularity.
We found a link to a blog – Linking other good sources of information is always a plus when we talk about SEO. This increases your authority and helps your website grow.
Add a mobile sitemap – If you have a responsive website your standard sitemap will work just fine. The only case you should have a separate mobiles sitemap is when you have a feature-phone version of your site (WAP/WML, etc).
Add an Apple icon – An Apple Icon is the graphic element that will be shown when a user saves your website on their home screen in iOS. If you are missing this element, iOS will generate a compressed thumbnail of your website and display it as the icon instead. This may lead to some visually unappealing results that you will not want your users to see.
We found a viewport metatag – Viewport Meta tags send information to search engines that your web page is optimized for mobile browsers which will prioritize them over websites with no such tags. You can find a listing of all viewport sizes here.