Apple Watch Series 1 vs Apple Watch Ultra 4

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Watch Series 1 compared with Watch Ultra 4

	AppleWatch Series 1	AppleWatch Ultra 4
Overview
Released
Released	September 2016	September 2026
Display
Case sizes
Case sizes	38 mm or 42 mm	49 mm
Panel
Panel	OLED	LTPO OLED
Peak brightness
Peak brightness	450 nits	3,000 nits (better)
Always-on display
Always-on display	No	Yes
Display detail
Display detail	Retina OLED with Force Touch; 272 x 340 pixels (38mm) or 312 x 390 pixels (42mm)	Always-On Retina display with wide-angle OLEDs and LTPO3; 1Hz refresh; 422 x 514 pixels at 326 ppi; 1,245 sq mm display area; 1 nit minimum brightness; Night Mode for Ultra watch faces
Screen protection
Screen protection	Strengthened Ion-X glass	Flat sapphire crystal front
Health and fitness
ECG
ECG	No	Yes
Blood oxygen
Blood oxygen	No	Yes
Skin temperature
Skin temperature	No	Yes
Sleep apnoea alerts
Sleep apnoea alerts	No	Yes
High blood pressure alerts
High blood pressure alerts	No	Yes
Body composition
Body composition	No	No
Fall detection
Fall detection	No	Yes
Crash detection
Crash detection	No	Yes
GPS
GPS	None	Dual-band (L1 and L5)
Water resistance
Water resistance	–	100 m
Sensors
Sensors	Optical heart-rate sensor, accelerometer, gyroscope and ambient light sensor	Health Sensing System with third-generation electrical heart sensor, always-on optical heart sensor, blood oxygen sensor and temperature sensor; depth gauge to 40 m; water temperature sensor; compass; always-on altimeter (–500 m to 9,000 m); high-g accelerometer; high dynamic range gyroscope; ambient light sensor
Health features
Health features	Heart-rate monitoring; Activity rings and Breathe app in watchOS 3	Readiness app; Vitals app (heart rate, respiratory rate, wrist temperature, blood oxygen, sleep duration and HRV); Recovery HRV; high-frequency background heart rate tracking; ECG app; Blood Oxygen app; irregular rhythm notifications; high and low heart rate notifications; hypertension notifications; sleep apnoea notifications; sleep stages and sleep score; Cycle Tracking with fertile window and retrospective ovulation estimates, perimenopause and menopause support; Medications; Mindfulness; Noise
Fitness features
Fitness features	Workout tracking; outdoor route tracking uses a paired iPhone's GPS (PhoneArena)	Customisable Action button with Precision Start; custom workouts; Training Load and Workout Effort; customisable heart rate zones; VO2 max; Race Route; Pacer; cadence, stride length, ground contact time, vertical oscillation and running power; multisport workouts; offline maps with custom route creation; elevation alerts; Backtrack; swimming with water temperature; recreational diving to 40 m with Depth app and third-party dive computer apps; cycling with power meters; GymKit
Safety features
Safety features	–	Emergency SOS and Find My via satellite; Emergency SOS; international emergency calling; Siren; Fall Detection; Crash Detection; Check In; Backtrack; Last Emergency Call Availability Waypoint; torch; noise monitoring
Battery and connections
Battery life (maker's claim)
Battery life (maker's claim)	Up to 18 hours	Up to 50 hours
In low-power mode
In low-power mode	–	Up to 84 hours
Mobile data option
Mobile data option	No	Yes
Works with
Works with	iPhone	iPhone
Chip
Chip	S1P	S11
Storage
Storage	8 GB	64 GB (better)
Battery life detail
Battery life detail	Built-in rechargeable lithium-ion battery	Up to 50 hours of normal use; up to 84 hours in Low Power Mode; up to 18 hours of outdoor workout, 25 hours in Extended Workout and 45 hours in Max Extended Workout
Charging
Charging	Magnetic charging cable	Fast charging to 80% in about 45 minutes; 15 minutes for up to 18 hours of normal use; 5 minutes for up to 10 hours of sleep tracking
Connectivity
Connectivity	Wi-Fi 802.11b/g/n at 2.4GHz; Bluetooth 4.2; Apple support's updated compatibility requirement is iPhone 5s with iOS 11 or later	GPS + Cellular only (model A3579) with 5G RedCap and LTE; satellite communications; Wi-Fi 4 (802.11n) at 2.4GHz and 5GHz; Bluetooth 5.3; second-generation Ultra Wideband chip; NFC for Apple Pay; precision dual-frequency GPS (GPS, Galileo, QZSS and BeiDou)
Storage
Storage	S1P dual-core processor name reported by Wareable; Apple specifications confirm a dual-core processor and 8 GB capacity	–
Design
Weight (lightest version)
Weight (lightest version)	25 g (better)	63 g
Software
Software	watchOS	watchOS
Case materials
Case materials	Anodised aluminium case and composite back; IPX7 under IEC 60529, splash and water resistant but submersion is not recommended	Grade 5 titanium case (100% recycled titanium) with ceramic and zirconia back; water resistant to 100 m (ISO 22810:2010); EN13319 recreational diving to 40 m; IP6X dust resistant; tested to MIL-STD 810H
Size
Size	38mm is 38.6 x 33.3 x 10.5 mm and 25 g; 42mm is 42.5 x 36.4 x 10.5 mm and 30 g; weights exclude the band	49 x 44 x 12 mm; 63.0 g (natural) or 63.1 g (black)
Bands
Bands	Sold with Sport Band; compatible with Sport, Woven Nylon, stainless steel and leather bands	Fits 130–210 mm wrists
Colours
Colours	Silver, Space Grey, Gold and Rose Gold aluminium	Natural or Black titanium
In the box
In the box	–	Apple Watch Ultra 4, strap, Apple Watch Magnetic Fast Charger to USB-C Cable (1 m)