Garmin Forerunner 70 vs Apple Watch Ultra 3: GPS Watch Comparison

Overview

The Garmin Forerunner 70 is an entry-level running watch targeting newer athletes who want Garmin's training tools at $249.99. The Apple Watch Ultra 3 is a premium titanium adventure watch aimed at serious triathletes and outdoor athletes, competing with the Garmin Fenix 8 and Forerunner 965. These two devices occupy opposite ends of the sport watch market in both price and capability.

Specs at a glance

Price: Forerunner 70 at $249.99 / £219.99 vs Apple Watch Ultra 3 at premium tier (roughly $799+)
Display: FR70 AMOLED vs Ultra 3 LTPO OLED (always-on, larger panel)
GPS: FR70 chipset unconfirmed vs Ultra 3 multi-band GNSS with dual-frequency satellite support
Battery life: FR70 GPS hours unconfirmed vs Ultra 3 adequate for up to Half Ironman, not suited for true ultra-endurance
Heart rate sensor: Both use wrist-based PPG optical sensors measuring blood volume changes via LED light
Other sensors: Both include SpO2, skin temperature, barometric altimeter; FR70 also includes HRV tracking
Build: FR70 weight unconfirmed vs Ultra 3 titanium case, heavier than dedicated running watches
Water resistance: FR70 unconfirmed vs Ultra 3 rated for open-water swimming and diving

GPS and tracking accuracy

The Apple Watch Ultra 3 uses multi-band dual-frequency GNSS, which is the current hardware standard for accurate positioning in challenging environments. However, real-world testing over a 10-mile London course showed the Ultra 3 struggling in certain segments against the Garmin Forerunner 965, which finished closer to the known reference distance. Multi-band hardware does not guarantee perfect accuracy in every situation, and the Ultra 3 shows inconsistency in dense urban canyons.

The Garmin Forerunner 70's GPS chipset has not been disclosed in available sources. Garmin's track record at this price tier is solid, but no hands-on data exists to compare it directly. Until the FR70 is officially released and tested, any GPS accuracy comparison between these two devices is speculative.

Battery life

The Apple Watch Ultra 3 handles standard training sessions and races up to Half Ironman distance in full GPS mode. For events beyond that range, its battery is a real constraint. Exact GPS hours have not been specified in reviewed sources, but the consensus from testing is clear: it is not a watch for 100-mile ultras or multi-day adventures without recharging.

The Forerunner 70's battery life in GPS mode has not been confirmed in available sourcing. This is a significant gap in the comparison and a reason to treat this article as a preliminary look rather than a definitive head-to-head.

For athletes: who wins?

Running (road): Ultra 3 for users already in the Apple ecosystem who want polished training metrics. FR70 is the pick for budget-conscious runners who want Garmin's training load and physiology tools without ecosystem lock-in.
Trail running: Ultra 3 wins on hardware durability and multi-band GPS. The titanium build and dive-rated water resistance suit demanding outdoor conditions. FR70 specs are too uncertain to recommend here.
Triathlon: Ultra 3. It is explicitly designed for triathletes up to Half Ironman distance, with open-water swim rating and full multisport modes. The FR70 is an entry-level device not positioned for triathlon use.
Recovery tracking: Both devices include HRV and skin temperature sensors for recovery monitoring. Garmin's physio stack has a longer track record for actionable recovery scores. The FR70 carries that same stack at a fraction of the Ultra 3's price, which is a genuine advantage if recovery data is the primary goal.

Verdict

The Apple Watch Ultra 3 is the stronger device for serious athletes who train across multiple disciplines, need reliable multi-band GPS, and live in the Apple ecosystem. It earns its premium price for triathletes and outdoor athletes who will push it hard. The Garmin Forerunner 70 is a compelling entry-level option on paper, but it cannot be recommended with confidence right now because it is an unconfirmed product with no verified specs, no GPS accuracy data, and no hands-on testing available. Buy the Ultra 3 if you are a committed athlete with the budget and an iPhone. Wait for full FR70 confirmation and independent testing before spending even $249.99 on an unverified device.