Freeplane - Freeplane is a powerful and free software for building mind maps.
Scikit-learn - scikit-learn (formerly scikits.learn) is an open source machine learning library for the Python programming language.
Linked Ideas - A macOS/iOS apps to treat ideas as links of concepts.
Pandas - Pandas is an open source library providing high-performance, easy-to-use data structures and data analysis tools for the Python.
OmniOutliner - OmniOutliner is a writing app for collecting information, outlining ideas, adding structure to any sort of writing.
NumPy - NumPy is the fundamental package for scientific computing with Python