Perhaps you want to highlight a “Tip of the Day” section on your SharePoint site or implement a Timesheet in which employees can enter their project hours. You can download these apps from the SharePoint Store for free instead of hiring a developer to design and implement it!
In the upper-right corner of the window, click the Settings icon (the small gear graphic).
On the menu that appears, click Add An App.
Click the app that you want to add to your site.
Enter a name for the new app.
Click Create.
You can read a brief description of each app by clicking the App Details link, which is located below the app’s icon, on the Apps You Can Add page.
In the upper-right corner of the window, click the Settings icon.
On the Your Apps page, on the Quick Launch bar, click SharePoint Store.
Click Add It, Buy It, or Try It.
If the app requests trust confirmation, follow any instructions that are presented and then click either Trust It or Cancel.
You must be a Site Owner or have Full Control permissions to add apps from either the SharePoint Store or an App Catalog.