Facebook Platform uses the OAuth 2.0 protocol for logging a user into your app. The Login button in the top right of this app, shown when you're logged out, is a good example.

Check out the mobile web app tutorial at developers.facebook.com/docs/mobile/web/build/

Logging the user in

If a user visit your site directly, you will need to ask them to login with Facebook.

Logging the user out

You should include a button to enable the user to log out. Also, you can include a button so that the user can uninstall your app.

Login using Facebook
Logout
Uninstall app

Asking for extended permissions

If your app needs more than this basic information to function, you must request specific permissions from the user. For example, you might prompt the user to grant access to their Likes in order to recommend related content for them.

Grant the 'user_likes' permission
You need to login before you can use this functionality.

Requests allows the user to invite their friends to the app, or to re-engage their friends so they come back to your app. Friends receive requests in Notifications on Facebook.

Check out the mobile web app tutorial at developers.facebook.com/docs/mobile/web/build/

Request

If you show the request dialog with no friend suggestions, it will automatically show friends that are using your app, as well as friends that have already used your app.

Send request

Invite friends not using app

The user can invite their friends that have not started using your application yet. This will help grow your mobile website virally.

Send invite
You need to login before you can use this functionality.

Request to app friends

If a friend of the active user needs to take an action in your mobile web app, you can prompt them to send a request. This can be used for re-engagement, like telling a friend it's their turn in a board game.

Send request
You need to login before you can use this functionality.

Request to targeted friend

If the user's friends need to take an action in your mobile website, you can prompt them to send a request. This can be used for things like telling a friend it is their turn in a board game.

Send request
You need to login before you can use this functionality.

Your app can prompt users to share on their own wall or their friend's wall.

Check out the mobile web app tutorial at developers.facebook.com/docs/mobile/web/build/

Publishing to the user's wall

This allows a user to post something to their own Wall, which means it will also appear in all of their friends' News Feeds on Facebook.

Publish to your wall

Publish to a friend's wall

This allows a user to post something to their friend's Wall, which means it will also appear in all of their mutual friends' News Feeds on Facebook.

Publish to friend's wall
You need to login before you can use this functionality.

The Graph API enables you to read and write data to Facebook. You can utilize what the user has liked, friends, photos, events, as well as most of the data that's available on Facebook.

Check out the mobile web app tutorial at developers.facebook.com/docs/mobile/web/build/

Get user's basic information

You can fetch the user's profile picture and name in order to personalize the experience for them.

Get your information
You need to login before you can use this functionality.

Get user's friends

To make your mobile web app social, you can fetch their friends' information like profile pictures and names.

Get your friends
You need to login before you can use this functionality.

Get user's recent check-ins

You can fetch fetch their previous Facebook Places check-ins.

Grant check-in permission
You need to login before you can use this functionality.
Get past check-ins

Check the user into a place

You can fetch Places near the user's current location and check the user in.

Grant check-in permission
You need to login before you can use this functionality.
Find nearby locations

Your app or game can prompt the user to pay for a virtual good by using Credits.

Check out the mobile web app tutorial at developers.facebook.com/docs/mobile/web/build/

Prompting the user to pay

This allows the user to pay for a virtual good in your app or game.

Prompt to Pay

Social plugins lets a user see what their friends have liked, commented on or shared on sites across the web. Currently, the only social plugin that's available is the Like button. More coming soon.

Check out the mobile web app tutorial at developers.facebook.com/docs/mobile/web/build/

Like button