Android Fundamentals is the foundation for the rest of the handbook. These questions cover the platform concepts that explain how Android applications are structured, how components communicate, and how work and state are owned across lifecycles.

The goal is not to memorise callbacks or API names. It is to understand why Android's core components exist, what responsibility each one owns, and what can go wrong when those boundaries are misunderstood.

What this section builds

The questions are arranged so that later concepts build on earlier ones. Together they introduce recurring engineering ideas such as platform layers, capability and lifetime, UI ownership, lifecycle transitions, Intent resolution, delegated permission, transient state transport, component boundaries, and work that can outlive a screen.

Use the interview-ready answer first, then go deeper only where you need more context. By the end of the section, you should be able to explain both the Android mechanism and the engineering reasoning behind it.

Questions

• AF-001 — What is Android?
• AF-002 — What is Context in Android?
• AF-003 — What is the difference between an Activity and a Fragment?
• AF-004 — Can you walk through the Activity lifecycle?
• AF-005 — Can you describe the Fragment lifecycle and Fragment view lifecycle?
• AF-006 — What is the difference between an explicit and implicit Intent?
• AF-007 — What is a PendingIntent and why is it needed?
• AF-008 — What is a Bundle and when would you use one?
• AF-009 — How do you pass data between Activities and Fragments?
• AF-010 — What is a Service?