| Number of Users | 3900 M | 1600 M | 1400 M | 400 M | 200-400 M (users est.) | 50-200 M (desktop users est.) | Unknown (niche/embedded) | 50 M | 50 M |
| First Release | In 2008 | In 2007 | In 1985 | In 1984 | In 2019 | In 1991 | 2000s (varies) | In 2011 | In 1993 |
| Lineage | Based on Linux. | Darwin-based; lineage back to the original UNIX. | MS-DOS roots; NT line started as a fork of OS/2. | Early versions were independent; now Darwin-based with UNIX lineage. | Huawei HarmonyOS; OpenHarmony open source; Linux on phones, microkernel in IoT | Linux kernel + GNU userland roots. | Linux kernel with non-GNU userland (BusyBox/musl). | Linux-based; Gentoo roots. | Forked from BSD; lineage back to the original UNIX. |
| Availability | Open-source core (AOSP) + proprietary services | Proprietary, closed source | Proprietary, closed source | Proprietary, closed source | Open-source core (OpenHarmony) + proprietary services | Free and open source (various distros) | Free and open source (various distros) | Proprietary; ChromiumOS is open source | Permissive open source |
| Company / Organization | Alphabet Inc. (US) | Apple Inc. (US) | Microsoft Corp. (US) | Apple Inc. (US) | Huawei Corp. (CN) + OpenAtom Foundation (CN) + OpenHarmony community (global) | Arch & Debian (community), Fedora (Red Hat, Inc.), Ubuntu (Canonical Ltd.) | Community + vendors (e.g., Alpine, OpenWrt). | Google Inc. (US) | FreeBSD Core Team (global) |
| License | GPLv2 | APSL 2.0 | Proprietary | APSL 2.0 | Apache 2.0 (OpenHarmony) + proprietary | GPLv2 | GPLv2 + mixed | GPLv2 | BSD 2-clause |
| --- | --- | --- | --- | --- | --- | --- | | --- | --- |
| Device Compatibility | Smartphone/Tablet/TV/Embedded | Smartphone/Tablet | Desktop/Laptop | Desktop/Laptop | Smartphone/Tablet/TV/IoT/Embedded | Desktop/Smartphone/Tablet/TV/Embedded | Embedded/routers/containers | Laptop/Desktop | Desktop/Server/Embedded |
| Typical Variants/Layers | OEM skins like One UI, ColorOS, HyperOS, and Pixel UI; forks include FireOS, LineageOS, or GrapheneOS. | iOS and iPadOS variants; no third-party distros. | Editions like Home, Pro, Enterprise, and Server. | macOS releases only (no distros). | HarmonyOS + OpenHarmony; OEM layers on top. | Distros such as Arch, Debian, Ubuntu, Fedora, RHEL, SUSE, Gentoo, Void, NixOS, and TinyCore. | Alpine, OpenWrt, Buildroot, Yocto-based images, KaiOS, SelfishOS. | ChromeOS and ChromeOS Flex; open-source ChromiumOS. | Derivatives like GhostBSD and HardenedBSD. |
| Areas of Use & Devices | Smartphones, tablets, TV | Apple smartphone/tablet | Desktop, gaming, enterprise | Professional desktop | Phones, tablets, wearables, IoT | Servers, desktop, alternative mobile | Routers, appliances, containers, IoT | Education, consumer laptops | Servers, NAS, embedded |
| Number of Variants | ~10-15 | 1 | 5 | 1 | 2 (HarmonyOS, OpenHarmony) | ~300+ ~5-8 | Many (embedded-focused) | 2-3 | 3 |
| --- | --- | --- | --- | --- | --- | --- | | --- | --- |
| Kernel | Linux :penguin: | XNU :apple: | Windows NT :window: | XNU :apple: | Harmony microkernel + Linux (phones) :penguin: | Linux :penguin: | Linux :penguin: | Linux :penguin: | FreeBSD :smiling_imp: |
| Kernel Type | Modified Linux | Hybrid XNU | Hybrid NT | Hybrid XNU | Microkernel + monolithic (Linux) | Monolithic Linux | Monolithic Linux | Monolithic Linux | Monolithic FreeBSD |
| Drivers | Kernel + HAL | IOKit | WDM/KMDF | IOKit | HDF (Harmony Driver Foundation) | Kernel modules | Kernel modules | Kernel modules | Native BSD kernel |
| Userland | Bionic libc | BSD | Win32/.NET | BSD | HarmonyOS framework + Ark runtime | GNU | BusyBox/musl (non-GNU) | GNU userland | BSD |
| Primary Userland | Android userland (toybox/toolbox + ART) | BSD userland | Win32/NT subsystem | BSD userland + Cocoa | HarmonyOS framework + Ark runtime | GNU coreutils + system utilities | BusyBox/toybox + minimal userland | GNU userland (Gentoo-based) | BSD base system |
| C Library | Bionic | libSystem (Darwin libc) | UCRT/MSVCRT | libSystem (Darwin libc) | musl (OpenHarmony) | glibc (most; musl in Alpine) | musl/uClibc | glibc | FreeBSD libc |
| Bootloader | OEM bootloader/fastboot/recovery | EFI + iBoot | Windows Boot Manager/UEFI/BIOS | EFI + boot.efi/UEFI | OEM bootloader/fastboot | GRUB/systemd-boot/LILO | U-Boot/GRUB (varies) | Coreboot + depthcharge (verified boot) | BIOS/UEFI/Boot0 |
| Init System | Android init | launchd | Service Control Manager | launchd | OpenHarmony init | systemd (most distros) | OpenRC/runit/busybox init (varies) | Upstart | rc.d + init |
| Display Server | SurfaceFlinger | UIKit + Core Animation | Win32/GDI + DWM | Quartz Compositor | SurfaceFlinger (phones); ArkUI/ACE | X11/Wayland | None/headless; X11/Wayland optional | Wayland (Chrome OS) | X11/Wayland |
| Window Management | N/A | N/A | DWM | Quartz Compositor | N/A | Mutter/KWin/Xfwm/Openbox/etc. | N/A or lightweight WMs (varies) | Aura | X11/Wayland WMs (varies) |
| Desktop Environment | N/A | N/A | Explorer shell | Aqua | N/A | GNOME/KDE/XFCE/Cinnamon/etc. | None; lightweight DEs (varies) | Chrome OS UI | KDE/GNOME/XFCE/etc. |
| Package Manager | Play Store/APK | App Store | Winget/Microsoft Store | App Store | AppGallery | apt/dnf/pacman | apk/opkg/none (varies) | Play Store + Chrome Web Store | pkg/ports |
| --- | --- | --- | --- | --- | --- | --- | | --- | --- |
| Architectures | ARM | ARM | x86/ARM | ARM/x86 | ARM | x86/ARM/RISC-V | ARM/MIPS/x86/RISC-V | x86/ARM | x86/ARM |
| App Model | APK sandbox | Signed apps | Executables | Signed apps | Harmony apps (Ark/Ability); Android compat (earlier) | Native binaries | Packages/static binaries | Web apps + Play Store (ARC) | Ports/pkg |
| Memory Management | LMK/zRAM | Aggressive Mach VM | NT VM | Mach VM | Hybrid; Linux VM + microkernel | Linux VM | Linux VM | Linux VM | BSD VM |
| File System | ext4/F2FS | APFS | NTFS | APFS | ext4/F2FS | ext4/Btrfs/XFS | ext4/squashfs/overlayfs | ext4 | UFS/ZFS |
| Process Scheduling | CFS + mobile optimizations | Mach | NT Scheduler | Mach + BSD | Microkernel scheduler + Linux CFS | CFS | CFS | CFS | ULE Scheduler |
| Security | SELinux enforcing | Full sandbox | ACL/UAC | SIP + sandbox | TEE + app sandbox | SELinux/AppArmor | Minimal; SELinux/AppArmor optional | Verified Boot + sandboxing | Jails |