How to study this site

The site has four study instruments. Each does something the others cannot, and using only one is why people read a whole documentation site and retain almost none of it.

TL;DR#

Paths decide what to read next. Without one, you will read the interesting pages and skip the ones that make them make sense.
Quizzes test whether you can explain the mechanism, not whether you recognise a word.
Flashcards keep the vocabulary alive between sessions, with spacing that widens as you prove you know it.
Cheat sheets are the reference you come back to when you are actually doing the work.
Read, then test, then space, then reference. In that order.

Mental model#

Learning a musical instrument is not listening to music. You listen to learn what good sounds like, then you practise scales, then you play until it is automatic, then you keep a chord chart nearby for the songs you have not memorised.

The four instruments here map to those four activities.

Where the analogy breaks#

Music practice is mostly physical repetition. Understanding a software mechanism is mostly explanation: if you can explain why Zygote forks rather than execs, you know it. That is why the quizzes ask "what would happen if" rather than "what is the name of".

The big picture#

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The Android stack, with the study instruments mapped onto it. Paths take you through the stack in a chosen order. Quizzes sit at the end of each page and test what you just read. Flashcards operate on vocabulary across the whole stack over weeks. Cheat sheets compress one layer into a single printable page for reference while working.

Deep dive#

Paths: the order matters#

The learning paths exist because the modules are not arranged for a beginner's first read. The platform-nerd path starts at the kernel; the app-developer path starts at components. Both are right for different people, and neither is right for everyone.

Each path tracks progress in your browser. The "next up" button is the whole interface: it removes the decision of what to read next, which is where most self-directed study stalls.

Quizzes: understanding, not trivia#

Every module's quiz mixes five question types. The multiple-choice questions are the least interesting; the ordering questions ("put the boot stages in order") and the explanation-backed "what would happen if" questions are the ones that find the gaps.

The rule when you get one wrong: re-read the section the question came from, not the whole page. Every explanation links to its anchor for exactly this reason.

Flashcards: spacing beats cramming#

The review queue uses SM-2, the classic spaced repetition algorithm. You grade each card from "again" to "easy", and the interval grows according to your grade and the card's history. Cards you struggle with come back sooner; cards you know disappear for months.

Two practical rules:

Review daily, briefly. Ten minutes a day beats an hour on Sunday, because spacing is the mechanism, not the total time.
Grade honestly. Grading "good" on a card you barely recalled corrupts the schedule.

The decks are generated from the glossary and from quiz questions, so they stay in sync with the pages.

Cheat sheets: for when you are working#

The cheat sheets are deliberately printable. They are not summaries of the pages; they are the reference card you keep open while doing the thing — the adb commands, the lifecycle callbacks, the API-to-version table, the dangerous permissions by group.

How it evolved#

usual →Read onceFeels productive, retains little.

better →Read + testRetrieval practice, the strongest single effect.

best →Read + test + spaceWhat the paths, quizzes and review queue implement.

Curiosity corner#

Flashcards are not only for facts. A card whose front is "why does Zygote fork instead of exec?" is a better card than one whose front is "what is a zygote?" — the second tests recognition, the first tests understanding.
The quizzes are generated from the same data as the pages, so an answer cannot drift away from the prose without the build failing.

Try it#

Open Review and do ten cards. Then open the paths and start the shortest one. That is the whole method.