The Salesforce SDK can be deployed directly to Sandbox or Developer
organizations by using the Deploy to Salesforce
functionality.
“Deploy to Salesforce” functionality is not owned or maintained by Box.
The SDK is also distributed as an unmanaged package:
Unmanaged packages can’t be upgraded once installed in a Salesforce org so
future upgrades will have to be applied by cloning the repositories locally
and updating classes from your IDE.