Meet Pocket Studio — a tour

Five minutes now, an hour saved later

You are one lesson away from building a real app. Before that, it is worth learning where things are — because in the next lesson you will be told to "tap Run", and it should be obvious where Run is rather than a small treasure hunt.

Pocket Studio looks busy at first. It is not. There are five places in it, you will live in three of them, and the other two are there when you need them.

The five places

1. Projects — the rack of half-finished pieces

A project is one folder holding everything one app needs: your code, its pictures, its text, and the settings that say how to build it.

The Projects screen lists every project you have. It is where you tap New Project to start one, and where you tap a project's name to open it. Right now yours is probably empty.

New Project asks you to pick a template — a starting skeleton so you are not staring at nothing. This course always uses the empty Jetpack Compose template, because it gives you the smallest project that still runs.

2. Editor — the bench

This is where you type. It is a real code editor, not a text box:

• Code completion — start typing Tex and it offers Text. Tap the suggestion instead of typing the rest. It is faster, and it cannot misspell.
• Go to definition — long-press a name like MaterialTheme and jump to where it was defined. This is how you read other people's code without guessing.
• Red underlines — the same idea as a spell-checker, except it is checking Kotlin grammar. A red underline means the compiler will refuse this line. Fix it before you build and you save yourself a four-minute round trip.

The editor shows about 60 characters per line, and it does not soft-wrap. A longer line does not fold onto a second row; it slides off the right edge and you have to scroll sideways to read it.

That single fact shapes this entire course.

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2val playerScoreThisRound = scoreFor(rolls, bonusMultiplier)

The top row is a 60-character ruler. The line under it just fits. One more word and you would be scrolling sideways to read your own code on a bus.

So every single line of code in this course is 60 characters or fewer. Not as a gimmick — it is the difference between code you can read on a phone and code you cannot.

3. Build — the noisy machine

Tap Build and you get a black panel that fills with text. That text is Gradle talking to you: which step it is on, what it downloaded, and whether it worked.

The important button lives here: Run, drawn as a triangle ▶. Pressing it does three things in a row, without asking:

1. Builds your project into an APK.
2. Installs that APK on this phone.
3. Opens the app.

There is also Stop (a square ■) for when a build is taking longer than you expected and you would like it to stop taking longer than you expected.

Lower down, or under a Logcat tab, is Logcat — the live stream of messages Android prints while your app is actually running. When an app closes unexpectedly, the reason is always in there. Lesson 0.6 teaches you to read it.

4. Terminal — the odd-tools drawer

A real command line, running on your phone. You can type Gradle commands by hand here:

./gradlew assembleDebug

You will almost never need it in this course — the Run button does the same job with fewer chances to mistype. It is listed here so that when you see a command in a forum post one day, you know where it goes.

5. Git — the logbook

Git takes a snapshot of your project whenever you ask, so you can look back at what changed and undo a bad afternoon. Pocket Studio has it built in — you never need a separate app or a website account.

You do not need Git today. You will want it by Part 5, and Lesson 0.7 gets you into the habit early, when the stakes are low.

The Assistant

There is an Assistant — an AI you can ask about your code. It is optional, and it needs your own Google Gemini API key before it will answer anything. If you do not have one, the Assistant simply sits there and nothing else stops working.

A word of advice you can take or leave: leave it switched off for Part 0 and Part 1. Right now, the thing you are training is the ability to read an error and think. An assistant that answers before you have thought is a fast way to finish the course having learned nothing.

What the Free tier gives you

Straight answer, because it matters before you start: the Free tier of Pocket Studio gives you a limited number of builds and produces debug APKs — apps signed with a throwaway key that install on your own phone instantly.

That is everything this course needs. Every app in Parts 0 through 6 is built and installed as a debug APK. Nothing you are about to do requires paying for anything.

The one habit worth forming because of the build limit: think before you press Run. Read your change, look for red underlines, then build. Pressing Run four times in a row hoping something changes is a bad habit anyway — it just costs you something visible here.