I have gone through https://github.com/AuthorizeNet/accept-sdk-android
and setup https://github.com/AuthorizeNet/accept-sample-android as per guidance, and also applied CLIENT_KEY and API_LOGIN_ID from my sandbox account.
I stuck into something here now, after EncryptTransactionCallback it comes to onEncryptionFinished() or onErrorReceived(). In my case it comes to onEncryptionFinished(), it returns getDataDescriptor() and getDataValue(). There is no proper guidance what needs to be done after it.