Interesting facts about Azure Digital Twin Service Preview

Interesting facts about Azure Digital Twin Service Preview

Currently the Azure Digital Twin Service is still in preview. There are some interesting facts and small issues you need to know before starting to try this out. To understand what Azure Digital Twin offers, it would be best to read my extended post about an introduction to Microsoft Digital Twin. So let’s start!

Availability of Digital Twin Preview

Or the lack of it. You are lucky if you already had a created Azure resource based on the Digital Twin service. At the moment Microsoft states :

Thank you for your interest in the Azure Digital Twins preview program. Due to overwhelming demand, the preview program is temporarily closed as we prepare for the upcoming release of new capabilities. As a result, you may not be able to create new Azure Digital Twins resources right now. Please continue checking back for new information.

So be careful not to throw your resource away. A good chance is that you are not able to create one again. I tried several locations worldwide without luck. Luckily I already had one.

Simulated device(s)

Microsoft has an interesting example which allows you to play around with the Azure Digital Twin service without having an actual device. It uses a separate project which communicates through the IoT hub to provide the Digital Twin simulated data.

IoT Hub… where is it?

Talking about IoT Hub. Wonder where that one is? It is there, but you cannot access it. It is automatically generated when the Azure Digital Twin was created. It will not appear in the list of resources in your Azure environment. Even worse… you can’t access it via Azure Powershell.

Digital Twin viewer

There is a great Digital Twin viewer. But you will get into an issue, when you have done the example before the viewer. The redirect URL of the example is the same as the viewer which causes issues by logging into Azure via the browser using the example. The best way is to change the port number of the redirect URL of the project. Add an additional URL to the App registration under the Azure Active Directory to support this.


There are several limitations using the Azure Digital Twin Preview. You are allowed to run only one Azure Digital Twin service at the time. There are rate and message limitations for Azure Digital Twin Management API, user-defined functions and device telemetry. Read about them here.


Playing around with Azure Digital Twin Preview is just great! As long as you understand the limitations you can try several things yourself without having an actual IoT device. It gives you a good understanding and ideas where you can use it for. We need to wait for general availability to start using it in businesses. There are some other interesting findings posted in the feedback hub which you can find here.