The Capture SDK is unaware of any networking implementations and requires you to set them in the builder of GiniCapture. The networking related logic is abstracted behind the GiniCaptureNetworkService interface which is used to upload, analyze and delete documents. You can view the reference documentation for details.
You can provide your own networking by implementing the GiniCaptureNetworkService interface and passing your instances to the builder of GiniCapture. Also, you can use Gini Bank API Library for Android or implement the communication with the Gini Bank API yourself.