Where can I find ubirch documentation on a custom code to communicate with the SIM?
You can find the backend API documentation on https://developer.ubirch.com/api.html. You can also take a look the code used by the ubirch testkit as an example. Setting up a ubirch testkit might also be a good choice for getting acquainted with the ubirch functionality before starting to develop your own code.
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Visit the 1NCE Shop and start connecting your IoT devices easily. Simply order your SIM cards, choose the desired type of SIM card and fill out all required forms. After the payment has been approved you get your cards within five to seven business days.