SymPy Editor vs PyLearn

Edit mathematics the way you read it. SymPy editor draws your expression as a real formula, and every piece of it responds to touch: tap a term to select it, type over it, pull it apart, or apply any function from SymPy, the Python computer algebra system that powers it all. The whole CAS runs on your phone. No account, no ads, no tracking, no network: CPython and SymPy are packaged inside the app, everything you type stays on your device, and it all works in airplane mode. EDIT FORMULAS, NOT CODE • Tap any sub-expression (a term, an exponent, a matrix entry) and edit it in place • Type over a selection, or place a caret between terms and insert • Tap an operator to change it: turn + into a product, make an equation, or delete it • Unwrap (cos θ → θ), isolate, delete, copy and paste sub-expressions • The SymPy source line under the formula follows it, and the formula follows the line: edit whichever you prefer ALL OF SYMPY, ONE TAP AWAY • Transform menu: simplify, expand, factor, partial fractions, trig rewriting and more • A menu per type: matrices offer determinant, inverse and transpose; integrals, sums, derivatives and limits offer evaluation; equations swap sides or collect everything on the left • A search box over every SymPy function, asking for the parameters each one needs • An "unevaluated" switch builds Integral(f, x) or Determinant(M) symbolically instead of computing it • A Symbols panel for assumptions (positive, real, integer…) and matrix symbols with their shapes EVERY STEP IS REMEMBERED • The history shows each step and what changed: in red what went, in green what came • Play it as a slideshow, at the speed you choose • Save it as a self-contained web page that works offline, or as a Python script that rebuilds every step with SymPy • Keep several sessions, each with its own history, all on your device FOR STUDENTS, TEACHERS AND SCIENTISTS Complete the square in front of a class, evaluate limits and integrals, manipulate matrices and N-dimensional arrays, and export the derivation when it is done. FREE AND OPEN SOURCE BSD 3-Clause, no strings attached. Worked derivations, the source code and a browser version are at https://upabjojr.github.io/sympy-editor/ — and the same editor runs in Jupyter notebooks (pip install sympy-editor).

Real Python, running on your phone. Not quizzes about Python — an editor, an interpreter, and tests that check what your code actually did. Every lesson gives you a problem, a code editor and a Run button. You write Python, run it, and see the output and the failing tests. The interpreter is real CPython, bundled inside the app, so it works on a plane, on the underground, and anywhere else with no signal. WHAT IS IN IT • 12 courses, 108 lessons, from your first variable to shipping an AI system • 27 quizzes and 6 capstone projects, graded against hidden tests • 12 cheatsheets for the things nobody remembers • 12 badges, XP and a streak, for the days when momentum is the hard part THE PATH Start with Python Basics: variables, loops, conditionals, functions. Then data structures, functions and objects, files and errors, data analysis, APIs and async. Then the part most courses stop before: LLM APIs and prompting, structured output and tool calling, embeddings and vector search, RAG systems, agents and tool use, and evals and shipping. Real practice with the things AI engineering is actually made of. NO ACCOUNT NEEDED The app opens and works with no sign-up. Make an account only if you want your progress on more than one device — it syncs when there is a connection and waits patiently when there is not. BUILT FOR A PHONE • A code editor with line numbers, syntax highlighting and a punctuation row, because semicolons and brackets are miserable on a phone keyboard • Adjustable text size everywhere, including inside code • Hints when you are stuck and a worked solution when you have had enough • Dark and light, and it respects the size you read at Python runs entirely on your device — no server executes your code. Signed out, nothing you write leaves the phone at all. With an account, your work syncs so you can carry on somewhere else, and the tutor sees the lesson and your code in order to answer questions about them.