Authorea Beta documents are more than just text and figures. Every Authorea document is a Git repository that can host data, source code and any other related supplemental material. You can add Jupyter / IPython Notebooks to a figure by adding a figure to an article and then clicking on the figure. The following menu will appear:
Click on Attach IPython Notebook and select a .ipynb file to attach. The Notebook will be added as a dataset in the Figure folder and can be run directly within your article by clicking the code icon next to the figure.