What kind of apps are you asking about? This runs full Windows 8.1, so you have 2 kinds of App Store immediately available -- the ASUS Vibe store, which is a software sourcer named Avantquest supplying Windows 7 compatible "Desktop" format applications, and the standard Windows 8 Store, run by Microsoft, which contains only "Metro" format applications which must conform to the MS Windows 8 design standards. If by "main stream apps", you are referring to applications like MS Office (Word, Excel, PowerPoint, etc.), Quicken, etc., these are commercial products which must be purchased through computer or office supply stores, either on-line or physical locations. There are open source alternates for many of these e.g., Apache OpenOffice(http://www.openoffice.org).