Really confused with Jupyter Notebook, Lab, extensions, and ipywidgets

Question

I want to create an interactive JupyterLab Notebook application, and I need to create a series of custom Widgets. So I started looking into this matter, and the more I look the

Answer 1

In general, stackoverflow question should try to only ask one question at the time. That being said, I'll try to answer the questions as best I can:

1. ipywidgets is the main way, yes. It is what people mean when they talk about notebook widgets.
2. There is an issue tracking general JS in jupyterlab on the jupyterlab repo.
3. @jupyter-widgets/jupyterlab-manager is the widgets for jupyterlab, yes, but you will still need the python code in ipywidgets. See http://ipywidgets.readthedocs.io/en/stable/user_install.html for details.
4. While it is true that one is JS and the other TS, the TS one also has all the bells and whistles. It is therefore also more complex. The JS one is more bare-bones and might therefore be better for understanding the most important bits.
5. I agree that both could do with better documentation! I've been meaning to do this for a while. The best way to make this happen is probably to open issues with specific questions on the respective repositories, and suggesting the explanation go in the README or similar. That way you can ensure that your pain-points gets addressed.
6. Given the large user base of widgets, I would consider it safe. While the bus factor isn't very high, people tend to step up if there is a drop in maintainers.
7. Yes, but using widgets for jupyterlab is still slightly high maintenance both for developers and users.
8. What you might want to study is Comms (http://jupyter-notebook.readthedocs.io/en/stable/comms.html), which is what widgets use under the hood for its synchronization. This is lower level though, so you will have to judge which is most suitable for you.