/ˈæn.dɹɔɪd/
n. — "Linux-based mobile OS enabling sideloading chaos across hardware buffet."
Android runs on modified Linux kernel with layered architecture (Kernel→HAL→Native Libraries→ART→Framework→Apps) powering 70%+ global smartphones via Google-led AOSP plus manufacturer skins. Unlike iOS's walled garden, Android supports sideloading, diverse SoCs (GPUs from ARM/Mali/Adreno), and Google Play Services for cloud sync while OEMs fragment versions/security patches across device zoo.
Key characteristics and concepts include:
- ART (Android Runtime) ahead-of-time compiler replacing Dalvik JIT, optimizing APK bytecode for ARM/x86 execution.
- HAL abstraction hiding Qualcomm/MediaTek/Nvidia silicon differences behind standard camera/sensor APIs.
- Project Treble modularizing vendor framework from AOSP, pretending OEM updates don't take 18 months.
- SELinux policies + Verified Boot preventing root exploits, Verified Boot 2.0 chaining hardware security.
In app launch, APK verifies → Zygote forks process → ART executes dex bytecode → SurfaceFlinger composites frames → Wayland/Vulkan submits to GPU—repeat across 10k+ device configs while Play Services mediates iOS-free cloud features.
An intuition anchor is to picture Android as global food court: Linux kernel common counter, HAL cooks device-specific recipes, ART serves optimized bytecode plates, Framework adds Google sauce—messy but feeds billions unlike iOS's single Michelin chef.