Although Office 365 offers an optimized UX for mobile devices, have you noticed that it doesn't offer the ability to search for information?
Building solutions with Office Graph
SharePoint 2013 does great job configuring things for you in search-driven publishing scenarios but there are a few things you should keep in mind to save yourself trouble.
Content Targeting with User Segments just works with Content Search Web Parts but some additional work is needed if you want to leverage it with the Search REST API.
Leveraging the Search REST API allows you to build rich search-driven solutions. If you’re not careful however, you might get results other than intended even though everything seems to be working correctly.