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And the Soon-to-be-released jupyterlab already have google-rt-collaboration plugin https://github.com/jupyterlab/jupyterlab-google-drive

Yes, another good one (that allows execution) is mybinder: https://mybinder.org

But it's great to have more options!

Those don't have Google docs style collaborative editting.

Colab is the "mature" verison of Jupyter Colaboratory, which was previously only used internally at Google.