Yes, we offer a sandbox environment that can be used for a variety of reasons. Most customers find it useful for:
How do I get access to the sandbox environment?
All production users (those with a fully signed up account) are allowed access to the sandbox that matches your pricing tier. E.g. if you have signed up for API access in production you will get access to APIs in our sandbox.
If you have a production account, just reach out to us and request a sandbox setup.
What environments does the testnet use?
You can take a look at our developer docs to see the environments that our sandbox environment points to. It is a completely separate environment requiring a different iOS App, usernames and PINs.