Why I don't see "properties"-column on my Azure-IoT-Central Device?

Note that when using the "Create default views" feature, you will only see a tile for displaying the property (even if it's writable). In order to have a tile where you can edit the property to change it on the device, you need to add a new view in the device template and select the form type ("Editing device and cloud data"). To add a new view, go to the device template, click on "Views" then select "Editing device and cloud data", then select your writable property from the list, save and publish the template, then you should see the writable property in this new Form column