Upgrading to iOS 13 may break the support for your apple pencil. We are working to resolve the issue.
The Apple Pencil (2nd generation) is partially supported in the Tinkercad iPad app.
The Apple Pencil (1st generation) is not fully supported by the Tinkercad iPad app. While it can be used for the Scribble shape and other workflows, the 1st generation Apple Pencil does not navigate the 3D design or resize handles well. We are following up with Apple on this bug and may offer full support in the future.