Maxima is recommended as a simple and free computer algebra system (CAS) that supports text features, while Mathematica is noted for its comprehensive capabilities but comes at a cost. Users suggest that both Maxima and Mathematica are relatively easy to learn, with Maple also being a viable option. Scientific Notebook is highlighted as a user-friendly word processor for math that integrates CAS functionality, allowing for easy insertion of mathematical symbols without needing to learn LaTeX. For mobile users, there is a search for CAS applications compatible with Windows Mobile, as well as software that can convert drawn math into digital form, with MathBrush mentioned as a potential solution.