MBurgerclass, also you should specify if you are using the development api or the standard API, be aware that different mode means different key, so a "development api key" would not work if you are using standard api.
MBurger.initialize()also may accept other parameters to control if you want MBurger SDK to cache your requests, you will find all information you need inside the Javadoc. Requesting anything from the SDK before initializing will result in an exception, so you shoud initialize on your
onCreatestarting Activity or on your custom
MBurgerApiActionInitializer. All these classes are used to obtain and map your custom objects from MBurger objects.