What Are the Basics of Android Development You Must Know?

Beginner Guide · Android Development

What Are the Basics of Android Development You Must Know?

SECTION 01Kotlin — the language to start with

Kotlin is Google's preferred language for Android and the right place to begin. It is concise, null-safe, and integrates seamlessly with Java. Learning Kotlin first gives you a smoother path than starting with Java and switching later.

Kotlin fundamentals to master

• Variables, data types, and null safety
• Functions, lambdas, and higher-order functions
• Classes, data classes, and inheritance
• Collections — lists, maps, sets, and their operations
• Coroutines — the modern way to handle asynchronous work

SECTION 02Android Studio — your build environment

Android Studio is where all Android code lives. It includes the emulator, build system (Gradle), debugging tools, and the layout preview. Learning to navigate it well saves hours of frustration.

What to get comfortable with

• Project structure — app module, Gradle files, source folders
• Running apps on an emulator and a physical device
• The Logcat window and basic debugging
• Layout inspector and preview pane
• Version control with Git inside Android Studio

SECTION 03Activities and the Android lifecycle

Activities are the screens of an Android app. Each activity has a lifecycle, and understanding that lifecycle is essential — most early bugs come from ignoring it.

What to understand

• The lifecycle methods — onCreate, onStart, onResume, onPause, onStop, onDestroy
• Intents — moving between screens and passing data
• The AndroidManifest.xml — declaring activities and permissions
• Back stack behaviour — what happens when the user presses back

SECTION 04Layouts and UI — XML vs Compose

Android offers two ways to build UI: the classic XML layouts and the modern Jetpack Compose. Both are worth understanding, but beginners should pick one path and go deep.

XML layouts (classic)
  → LinearLayout, ConstraintLayout, FrameLayout
  → Define UI in XML, bind in Kotlin
  → Uses findViewById or ViewBinding

Jetpack Compose (modern)
  → UI written in Kotlin code
  → Declarative style, like React
  → Google's recommended approach

Either way, you must learn:
  → Layout hierarchy
  → Responsive design
  → Accessibility basics
  → Handling screen sizes

Which one to choose first:

If you are learning in 2026
  → Start with Compose
  → It is Google's recommended direction
  → Cleaner mental model for UI

If you are joining an existing team
  → Learn XML + ViewBinding first
  → Many production apps still use it
  → Then transition to Compose

Best long-term approach
  → Learn both
  → Understand how they map to the same UI
  → Build one screen in each

SECTION 05State, ViewModel, and data flow

State is what makes an app feel alive — the data the UI shows and how it changes. Managing state well is the difference between a smooth app and a buggy one.

Core concepts

• UI state — what the screen currently shows
• ViewModel — the recommended way to hold UI state across config changes
• State hoisting — the pattern of lifting state up
• LiveData or StateFlow — observing state changes in Compose and Views
• Handling configuration changes — rotation, dark mode, and language

SECTION 06Data storage and APIs

Real apps talk to the outside world. You need to store data locally and fetch data from remote servers. These two skills unlock most practical app ideas.

SECTION 07Building your first real app

The fastest way to learn Android is to ship a real app — no matter how small. Pick a project, build it end to end, and publish it on GitHub (or the Play Store, if you are ready).

1. Pick a small scope. A to-do app, a weather app, or a simple notes app is enough.
2. Build one screen at a time. Do not try to build everything before running the app.
3. Connect to real data. Use a public API or local storage — not hardcoded values.
4. Add basic testing. Even one unit test and one UI test teach you how Android testing works.
5. Publish on GitHub. Write a clear README that explains the app and how to run it.
6. Iterate. Add one feature per week — and ship each improvement.

SECTION 08Test yourself — Android basics

SECTION 09Frequently asked questions

SECTION 10Related reads