1.) Log in or sign up in Facebook and go to https://developers.facebook.com/

2.) Click -> Add a new App

3.) Enter "Display Name", "Contact Email" and Press "Create App ID"

4.) Press "Set Up" for "Facebook Login" item

5.) Select "Android"

6.) Click "I already installed the Android SDK"

7.) In section 3 "Tell Us about Your Android Project": Enter "Package Name", "Default Activity Class Name" and press "Save" and Press "Continue"

8.) In section 4 "Add Your Development and Release Key Hashes": You can see how to generate key hashes
Please generate and enter you key hashes, Press "Save" and Press "Continue"

9.) In next sections "8. Add the Facebook Login Button", "9. Register a Callback" and "10. Check Login Status" Press "Next" button

10.) Go to Settings->Basic and enter you data information^

11.) In topbar press slider:

12.) In dialog box "Make App Public?" Press "Confirm"

13.) Copy you "Facebook App ID" to file "res/values/strings.xml" (Android Project), constant "facebook_app_id" and change constant "fb_login_protocol_scheme"

14.) The "Facebook Login" setting for the Android app is complete. If you use the web version with the application for Facebook (for products: My Social Network, Dating App and QA Chat) - we continue to configure.
Go to section "Facebook Login -> Quickstart" and Click "Web"

15.) Enter "Site URL" and Press "Save", also Press "Continue"

16.) In sections "2. Set Up the Facebook SDK for Javascript", "3. Check Login Status" and "4. Add the Facebook Login Button" Press "Next"

17.) Enter you "Valid OAuth Redirect URIs" and Press "Save Changes".

For Sell and Buy Today project urls: https://mysite.com/facebook/connect and https://mysite.com/facebook/auth

For Dating App and My Social Network project urls: https://mysite.com/facebook/connect and https://mysite.com/facebook/login

18.) I recommend that you read this Facebook statement

19.) Go to "Settings->Basic". Copy "App ID" and "App Secret" to you "db.inc.php" config file (change constants "FACEBOOK_APP_ID" and "FACEBOOK_APP_SECRET")