To initialize the SDK, add the following to your Application subclass; including your Publishable Key in the initialize method.
You should also include the UI SDK and initialize that as well. However in order to properly utilize the UI SDK a payment provider is required. Currently we only support Stripe as a payment provider so be sure to include that as well.
For this you must subclass the Application class and set it as the application in your AndroidManifest.xml. If you haven't done so already, create a class like above in your main application's project and be sure to add it to the application tag in your manifest like below