The coding exam practice app that makes you type it.
POLYGLOT is a retro terminal study app for Android. Twelve coding and data tracks, real interpreters that run what you write, and an exam simulator built around the dates on your calendar. No ads, no account, no connection required.
Free to download. One time $4.99 unlock opens all 12 tracks.
This is the whole app, running.
A lesson, a wrong answer, the diagnosis that follows it, and the exam board. Nothing here is a mockup.
Sound on. The voiceover walks the loop.
Your code actually runs. That is the whole point.
Most study apps grade you on multiple choice. POLYGLOT ships real engines: a WebAssembly CPython interpreter with NumPy, live JavaScript execution, a working SQL engine with JOINs and GROUP BY, a pandas DataFrame engine, real regex testing, and a simulated filesystem and git repository.
That means NumPy practice happens in NumPy, not in a quiz about NumPy. A pandas practice problem is graded by running the DataFrame operation and checking the frame that comes back. A SQL question is answered by a query engine that will happily tell you your JOIN returned nothing.
>>> arr = np.array([10, 20, 30, 40, 50])
>>> arr[1:4]
array([20, 30, 40])
Twelve tracks
It finds the exact character you got wrong.
A wrong answer in POLYGLOT does not just turn red. The app performs a character level diagnosis: it credits the part you got right, points at the exact slip, and then explains why in plain English with an analogy you can keep.
Type arr[1:3] when the answer is arr[1:4] and it will tell you the slip is at character 7, that the end of a slice is exclusive, and that stopping before index 3 is why you got two items instead of three. Type a bracket where a parenthesis belongs and it will explain that parentheses call a function while brackets index into data.
That is the loop that turns a wrong answer into something you actually keep.
Built around your actual exam date.
Register the exams you are really sitting and the tracks each one covers. POLYGLOT builds the countdown, generates fresh ten question simulations scoped to that exam, grades them A to F, and keeps a live readiness score that aims drills at whatever you keep missing.
Homework mode takes multi line Python problems and grades them by running them, so any approach that produces the right output passes. There is no hidden preferred solution to guess at.
Study habits, enforced by the app.
Spaced repetition
Material comes back on a schedule instead of when you happen to feel like revisiting it, with surprise flashback questions pulled from work you did days ago.
Predict before reveal
You are asked what the code will output before the answer appears. Committing to a prediction is what exposes the gap between recognising syntax and understanding it.
Mental model debriefs
Each course ends with a debrief on the model behind it, not a score. The goal is that you can explain why the language behaves the way it does.
Streaks you can defend
XP, levels and ranks, plus streaks with earnable streak freezes so one bad week does not delete a month of momentum.
Survival mode
A run that ends when you do. Useful for finding the exact point where your recall falls apart under pressure, which is the point an exam will find too.
Things to collect
Six unlockable phosphor themes, four collectible ASCII companions, and a shareable Operator License card that records your rank and the tracks you have cleared.
A terminal coding game that grades like a tutor.
Free to start. One payment, if ever.
The full Python track, daily challenges and drills are free forever. No advertising, no account, no tracking.
A single one time in app unlock that opens all 12 tracks. Not a subscription, and it does not expire.
POLYGLOT works fully offline, keeps no account and collects no tracking data. Your progress backs up as plain text you can read, keep and move yourself. The details are in the POLYGLOT privacy policy.
Straight answers.
Put it on your phone before the next exam.
A data analytics study app that fits in the gaps in your day, and a Python exam prep app that will not let you fake it.