Amazfit Cheetah 2 Ultra vs Apple Watch Ultra 3: Which Wins?

Overview

The Amazfit Cheetah 2 Ultra targets serious runners who want advanced biometric tracking, including muscle oxygen saturation (SmO2), at a mid-to-upper price point around £400. The Apple Watch Ultra 3 sits firmly in the premium tier, offering a polished all-around sports and smartwatch experience for athletes who live in the Apple ecosystem. If you train hard and want the best daily smartwatch integration, the Apple Watch Ultra 3 is the obvious orbit. If you want cutting-edge running-specific sensors without paying flagship Apple prices, the Cheetah 2 Ultra makes a case for itself.

Specs at a glance

GPS: Both use multi-band GNSS; Apple Watch Ultra 3 confirmed dual-frequency; Amazfit chipset unconfirmed
Battery life: Apple Watch Ultra 3 insufficient for ultra-endurance beyond Half Ironman in full GPS mode; Amazfit Cheetah 2 Ultra battery not confirmed in available data
Heart rate sensor: Both use wrist optical PPG measuring blood volume changes via LED light, not electrical impulses
SpO2: Both include optical blood oxygen saturation monitoring
SmO2: Amazfit Cheetah 2 Ultra includes muscle oxygen saturation sensor; Apple Watch Ultra 3 does not
Display: Apple Watch Ultra 3 uses LTPO OLED with always-on; Amazfit display unconfirmed
Build: Apple Watch Ultra 3 uses titanium, heavier than dedicated running watches; Amazfit weight unconfirmed
Price tier: Amazfit approximately £400-plus; Apple Watch Ultra 3 is a premium flagship with a significantly higher price

GPS and tracking accuracy

The Apple Watch Ultra 3 scored 88/100 in over 100 hours of sports testing, but GPS consistency is a real weakness. In a 10-mile London course test benchmarked against four watches including the Garmin Forerunner 965, the Ultra 3 struggled in specific segments, with the FR965 outperforming it in those stretches. For urban running with tall buildings and signal interference, that inconsistency matters.

The Amazfit Cheetah 2 Ultra's GPS chipset details are unconfirmed, so a direct GPS head-to-head cannot be made honestly. What is confirmed is strong HR tracking accuracy across difficult conditions. In a HYROX simulation at 33 degrees Celsius, wrist optical PPG sensors are at a significant disadvantage due to sweat and high skin perfusion, yet the Cheetah 2 Ultra showed near-zero bias against three reference devices: the Whoop MG, the Garmin HRM-600 chest strap (which measures electrical impulses via ECG, not optical PPG), and the Polar Verity Sense optical arm band. That is a meaningful result in a genuinely hard environment.

Battery life

The Apple Watch Ultra 3 has enough battery for most athletes training up to Half Ironman distances in full GPS mode, but it cannot cover true ultra-endurance events at that setting. For a watch priced at the premium tier competing with the Garmin Fenix 8 series, that is a notable limitation. Garmin's flagship watches offer substantially longer GPS endurance.

The Amazfit Cheetah 2 Ultra's battery life figures are not confirmed in available review data, which makes a direct hours comparison impossible. This is a gap in the available information, not a dismissal of the watch.

For athletes: who wins?

Running (road): Amazfit Cheetah 2 Ultra, based on strong HR accuracy under hard conditions and the SmO2 sensor for training zone insight. Apple Watch Ultra 3 GPS inconsistency in urban environments is a drawback for runners who care about precise pace data.
Trail and outdoor adventure: Apple Watch Ultra 3. Titanium build, confirmed diving-rated water resistance, and a mature ecosystem of navigation features give it the edge for multi-terrain use.
Triathlon: Apple Watch Ultra 3 for up to Half Ironman. Its multi-sport modes and polished transitions are well-suited to the format, though battery limits rule it out for full Ironman distances in full GPS mode.
Recovery and biometric depth: Amazfit Cheetah 2 Ultra. SmO2 monitoring adds a layer of muscle-level data that the Apple Watch Ultra 3 simply does not have. For athletes training by feel and physiological markers, that sensor is a genuine differentiator.

Verdict

The Apple Watch Ultra 3 is the better all-around device for most users, particularly those already in the Apple ecosystem who want a single watch for training, racing up to Half Ironman, and daily smartwatch use. Its weaknesses, GPS inconsistency in dense urban environments and battery limits for ultra-endurance, are real but acceptable for its target user. The Amazfit Cheetah 2 Ultra punches above its price with strong HR accuracy and a unique SmO2 sensor, but too many specs remain unconfirmed to recommend it with full confidence. Buy the Apple Watch Ultra 3 if you want a proven, premium all-rounder. Buy the Amazfit Cheetah 2 Ultra if you are a dedicated runner focused on biometric depth and want to spend significantly less than Apple's flagship price.