@fomightez and @carreau - Thanks so much for answering my questions!
The services I included in my comparison are Binder, Kaggle Kernels, Google Colaboratory, Azure Notebooks, CoCalc, and Datalore. (Datalore uses its own file format and is the furthest from the classic Jupyter Notebook interface, but it met all my criteria for inclusion, including that you can import/export the ipynb format.)
I didn’t include any services that only give access to the JupyterLab interface (such as Notebooks AI, Kyso, and CyVerse).
I didn’t include IBM Watson Studio Cloud because the process of setting up was cumbersome, the interface is complicated, and I ran into lots of errors during my testing.
I didn’t include any paid-only services (such as Crestle.ai, Paperspace, and Salamander).
Thanks so much for your list! Since I’m only comparing free services, that excludes SageMaker, R-Brain, and Datalab (which is free but incurs “usage” costs). Gryd has a free plan, but only for people with an academic email address. Code Ocean is similar, in that the free plan is severely limited unless you have an academic email address. All of these are potentially excellent options for some people, but my particular comparison is focused on free services that anyone can use.
Thanks again! If anyone decides they would like to give my draft of the Binder section a read, let me know. Regardless, I’ll post here once the article is live!