In August 2012, Microsoft officially launched its plan for Office and SharePoint Stores for marketing, selling and deploying apps from Microsoft and third-party developers.

On February 3, 2014, the company made "generally available" (GA) apps built for and around Microsoft Access. With that GA designation, Microsoft added to its Office Stores yet another, officially sanctioned category of apps to complement its already unveiled app categories, including Word apps, Excel apps, Mail apps and Project apps
Read more at: Microsoft gives Access Store apps the general-availability green light | ZDNet