The apps for SharePoint infographics published by Microsoft are really handy when it comes to understanding SharePoint apps. Learn what you can do with SharePoint apps and the various features, benefits, limitations (considerations) and hosting options you have when planning for SharePoint apps.
Download the pdfs from here: http://www.microsoft.com/en-us/download/details.aspx?id=42029
View infographics online: http://msdn.microsoft.com/en-us/library/office/dn833464.aspx
