Create hash key for Facebook app development

 Use following command to create a hash key.

keytool -exportcert -alias androiddebugkey -keystore ~/.android/debug.keystore | openssl sha1 -binary | openssl base64

Use password as : android

For release version use following command: 

keytool -exportcert -alias "alias of keystore" -keystore "Your path to the keystore when signing app" | openssl sha1 -binary | openssl base64