Observable - Interactive code examples/posts
Soulver - Soulver is a software application that functions as a calculator that allows you type a continuous stream of information rather than having to input data into multiple cells.
nbviewer.org - Rackspace server host Jupyter Notebooks from your github repo
Soulver 3 for Mac - A smart notepad with a built in calculator
Jupyter - Project Jupyter exists to develop open-source software, open-standards, and services for interactive computing across dozens of programming languages. Ready to get started? Try it in your browser Install the Notebook.
Numi App - Numi is a beautiful text calculator for Mac.