iOS 13
i
Developer	Apple
Announced	June 3, 2019 (WWDC)
Initial release	September 19, 2019
Final release	13.7 (September 1, 2020)
Launch devices	iPhone 11 · iPhone 11 Pro · iPhone 11 Pro Max
Preceded by	iOS 12
Succeeded by	iOS 14

iOS 13 is the thirteenth major release of iOS, released on September 19, 2019, with the iPhone 11 generation. Its face was Dark Mode — the system-wide dark appearance, scheduled or manual, that OLED iPhones had begged for — and its structure changed the platform family: the iPad's build split off as iPadOS, ending "iOS" as the tablet's name and freeing the two interfaces to diverge.

Privacy carried the strategic weight: Sign in with Apple offered an OAuth alternative with relay email addresses and mandatory placement rules that rattled the identity industry, while location permissions gained "just once" and background-tracking alerts. The launch itself was the platform's messiest since iOS 11 — 13.0 was superseded by 13.1 within five days, and the cycle's bug cadence pushed Apple to reorganize how iOS releases are internally tested and staged.

Dark Mode; Sign in with Apple; the QuickPath swipe keyboard; a rebuilt Reminders; Photos with a curated day/month/year browser and comprehensive editing (including video); Memoji stickers; Look Around in Maps; HomeKit Secure Video; Silence Unknown Callers; ultra-wideband support for the iPhone 11's U1 chip; and Low Data Mode. Downloads got dramatically smaller, and app launches roughly doubled in speed over iOS 12.

iPhone 11/Pro/Pro Max, iPhone XS/XR/X generations, iPhone 8, iPhone 7, iPhone 6s, iPhone SE, and the seventh-generation iPod touch — dropping the iPhone 5s, iPhone 6 generation, and the last 1 GB-RAM devices.

Dark Mode became a permanent system dimension and web standard (`prefers-color-scheme` adoption traces to this cycle); Sign in with Apple institutionalized privacy as a competitive weapon; and the iPadOS split defined the multi-OS Apple platform family that now spans six systems. Internally, its troubled launch reshaped Apple's release engineering — daily builds gated by default-off feature flags — which the smoother cycles that followed are credited to.