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Apex 4 (42mm) vs D2 Air X15

Coros Apex 4 (42mm) vs Garmin D2 Air X15

What Apex 4 (42mm) does better (5) and where D2 Air X15 wins (7) — every spec side by side.

Coros · 2025Apex 4 (42mm)

5.0Score

5 advantages≈ $430

Higher score

Garmin · 2025D2 Air X15

4.9Score

7 advantages≈ $650

3.4Display6.5

5.4Battery life3.2

4.9Health tracking8.3

4.6Sports & outdoor6.1

6.5Smart features3.2

4.8Build & durability3.7

Dimensions

Size comparison

Apex 4 (42mm)D2 Air X15

	Apex 4 (42mm)	D2 Air X15	Difference
Height	42.6 mm	45 mm	−2.4 mm
Width	42.6 mm	45 mm	−2.4 mm
Thickness	14 mm	12.5 mm	+1.5 mm
Weight	56 g	38 g	+18 g

Drawn to the same scale from the official dimensions (front and side).

Why is Apex 4 (42mm) better than D2 Air X15?

Battery life (smartwatch mode)15 days vs 10 days+50%
GPS battery life34 h vs 20 h+70%
Storage32 GB vs 8 GB4×
Sapphire crystalYes · D2 Air X15: No
GPS battery life (dual-band)26 h vs 17 h+53%

Why is D2 Air X15 better than Apex 4 (42mm)?

AMOLED / OLED displayNo · Apex 4 (42mm): Yes
Weight56 g vs 38 g+47%
Sport profiles36 vs 932.6×
Screen size1.2″ vs 1.4″+17%
Resolution (width)240 px vs 454 px+89%
Pixel density200 ppi vs 324 ppi+62%
Thickness14 mm vs 12.5 mm+12%

Specifications

Side by side

Only differences	Coros Apex 4 (42mm)≈ $4305.0	Garmin D2 Air X15≈ $6504.9
Design & durability
Case size	43 mm	45 mm
Weight	56 g	38 g
Thickness	14 mm	12.5 mm
Height	42.6 mm	45 mm
Width	42.6 mm	45 mm
Case material	Titanium	Stainless steel
Sapphire crystal	Yes	No
Lens / cover glass	Sapphire Glass	Corning® Gorilla® Glass 3
Strap material	Silicone / Nylon	silicone
Water resistance	5 ATM	5 ATM
Water rating (maker)	5 ATM	5 ATM
Display
Screen size	1.2″	1.4″
Display technology	Memory-in-pixel (transflective)	AMOLED
Panel	3rd Generation Memory-in-Pixel touch screen	AMOLED
AMOLED / OLED display	No	Yes
Always-on display	Yes	Yes
Touchscreen	Yes	Yes
Resolution (width)	240 px	454 px
Resolution (height)	240 px	454 px
Pixel density	200 ppi	324 ppi
Battery
Battery life (smartwatch mode)	15 days	10 days
Battery life with always-on display	—	4 days
Battery saver mode	—	25 days
GPS battery life	34 h	20 h
GPS battery life (dual-band)	26 h	17 h
Battery type	—	Lithium ion
Wireless charging	—	No
Charging	—	Garmin proprietary plug charger
Health sensors
Optical heart rate	Yes	Yes
Blood oxygen (SpO2)	Yes	Yes
ECG	Yes	Yes
Skin temperature	—	Yes
Temperature sensor	Yes	Yes
HRV tracking	Yes	Yes
Sleep tracking	Yes	Yes
Sensors	Speaker to take hands-free calls or play activity alerts out-loud., Dual-Microphone with Noise Reduction, Optical Heart Rate Monitor, Barometric Altimeter, Accelerometer, Gyroscope, 3D Compass, Thermometer ), Optical Pulse Oximeter, Electrical Heart Rate Sensor for HRV and Wellness Checks	GPS, GLONASS, Galileo, QZSS, BeiDou, Elevate wrist heart rate monitor, Pulse Ox blood oxygen saturation monitor, Barometric altimeter, Compass, Gyroscope, Accelerometer, Thermometer, Ambient light sensor
Sports & navigation
Built-in GPS	Yes	Yes
Dual-band GPS	Yes	Yes
Satellite systems	GLONASS, GALILEO, BDS, QZSS	GLONASS, GALILEO, BDS, QZSS
Offline maps	Yes	—
Barometric altimeter	Yes	Yes
Compass	Yes	Yes
Multisport / triathlon mode	Yes	Yes
Sport profiles	36	93
LED flashlight	—	Yes
Connectivity
NFC payments	—	Yes
Wi-Fi	Wi-Fi 4	Wi-Fi 4
ANT+ sensors	—	Yes
Smart features
Calls from the wrist	Yes	Yes
Speaker	Yes	Yes
Microphone	Yes	Yes
Voice assistant	—	Yes
Music on the watch	Yes	Yes
Storage	32 GB	8 GB
Third-party apps	—	Yes
Platform
Operating system	—	Garmin OS
Platform	Proprietary	Proprietary
Works with	—	iOS, Android

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