You can use either watch without carrying your phone for workouts, GPS tracking and prepared offline content. Staying connected is different: Apple Watch Ultra 4 needs its GPS + Cellular version and a supported carrier plan for cellular service; Garmin fēnix 9 Pro needs the inReach version and an active inReach plan for supported LTE or satellite communications. What works depends on your location, connection mode and setup.
What “without your phone” means
A watch can operate independently for some tasks without an internet connection, but calls, messages, streaming and other connected services need a route to a network. That route may be cellular, Wi-Fi or—on supported models and in supported conditions—satellite service. Offline features such as workout tracking or audio already downloaded to the watch are a separate category.
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Neither model should be treated as a complete phone replacement. The useful question is whether the feature you need works offline, over cellular, over Wi-Fi or by satellite.
Apple Watch Ultra 4: set it up for phone-free use
For calls and cellular data, choose GPS + Cellular
To use cellular services away from the paired iPhone, you need the GPS + Cellular Ultra 4 and an active plan from a supported carrier. Apple lists calls, texts, notifications and streaming among the uses for cellular service away from the iPhone. Carrier support, plan terms and compatible models vary by country and region; Apple says no single cellular model works worldwide. Check Apple’s carrier list for the place where you will use the watch.
#1 Best Overall
![Apple Watch Ultra 3 [GPS + Cellular 49mm] Running & Multisport Smartwatch w/Rugged Titanium Case w/Blue/Bright Blue Trail Loop - M/L. Satellite Communications, Advanced Health & Fitness Tracking](https://m.media-amazon.com/images/I/51SKumOyv8L._SL160_.jpg)
- RUGGED AND READY TO GO—The ultimate sports and adventure smartwatch is built to last with an extremely tough titanium case and a strong sapphire crystal display. Water resistant up to 100m—it’s great for swimmers, divers, and fans of high-speed water sports.*
- A FULL-FEATURED HEALTH TRACKER—Ultra 3 can take an ECG* and check your heart rhythm for signs of AFib—right from your wrist. The smartwatch sends alerts for possible hypertension,* an irregular heart rhythm,* or an unusually high or low heart rate. You can view your overnight health tracking metrics with the Vitals app,* track your sleep score, and take readings of your blood oxygen.*
- ULTIMATE RUNNING AND WORKOUT COMPANION—A superior fitness tracker for marathoners, triathletes, mountain bikers, backcountry hikers, and mountain climbers, Ultra 3 provides precision dual-frequency GPS, Pacer, Heart Rate Zones, Custom Workouts, running power, Workout Buddy powered by Apple Intelligence from your nearby iPhone,* training load, and more.
- KEEP HELP CLOSE AT HAND—Ultra 3 is a smartwatch that can detect a hard fall or severe car crash* and automatically help connect you to emergency services and notify your emergency contacts. Check In can automatically notify a loved one when you’ve arrived at your destination.
- MULTIDAY BATTERY LIFE—Ultra 3 is a smartwatch that’s engineered to give you even longer battery life. It’s perfect for trail runners—with up to 42 hours of normal use and up to 72 hours in Low Power Mode.* Track a workout with full GPS and heart rate monitoring for up to 20 hours in Low Power Mode.*
Apple announced Ultra 4 on September 9, 2026. Its press release says Workout Buddy can work without the iPhone nearby when Wi-Fi or cellular is available, with Bluetooth headphones required. This is phone-free, but not offline: the feature still needs network access. Apple’s announcement gives the product details.
Wi-Fi can provide another connection
If the watch can join a Wi-Fi network, Apple lists services such as Siri, Maps, weather, podcasts, music streaming, email and Walkie-Talkie as available while connected. Calls over Wi-Fi depend on Wi-Fi Calling being enabled where supported. Message delivery is not uniform: SMS/MMS and some third-party push notifications may still require the paired iPhone to be powered on and connected to Wi-Fi or cellular, even when it is not nearby. See Apple’s guide to using Apple Watch without its paired iPhone nearby.
Rank #2
![Apple Watch Ultra 3 [GPS + Cellular 49mm] Running & Multisport Smartwatch w/Rugged Titanium Case w/Black Titanium Milanese Loop - L. Satellite Communications, Advanced Health & Fitness Tracking](https://m.media-amazon.com/images/I/51x8F3QDUWL._SL160_.jpg)
- RUGGED AND READY TO GO—The ultimate sports and adventure smartwatch is built to last with an extremely tough titanium case and a strong sapphire crystal display. Water resistant up to 100m—it’s great for swimmers, divers, and fans of high-speed water sports.*
- A FULL-FEATURED HEALTH TRACKER—Ultra 3 can take an ECG* and check your heart rhythm for signs of AFib—right from your wrist. The smartwatch sends alerts for possible hypertension,* an irregular heart rhythm,* or an unusually high or low heart rate. You can view your overnight health tracking metrics with the Vitals app,* track your sleep score, and take readings of your blood oxygen.*
- ULTIMATE RUNNING AND WORKOUT COMPANION—A superior fitness tracker for marathoners, triathletes, mountain bikers, backcountry hikers, and mountain climbers, Ultra 3 provides precision dual-frequency GPS, Pacer, Heart Rate Zones, Custom Workouts, running power, Workout Buddy powered by Apple Intelligence from your nearby iPhone,* training load, and more.
- KEEP HELP CLOSE AT HAND—Ultra 3 is a smartwatch that can detect a hard fall or severe car crash* and automatically help connect you to emergency services and notify your emergency contacts. Check In can automatically notify a loved one when you’ve arrived at your destination.
- MULTIDAY BATTERY LIFE—Ultra 3 is a smartwatch that’s engineered to give you even longer battery life. It’s perfect for trail runners—with up to 42 hours of normal use and up to 72 hours in Low Power Mode.* Track a workout with full GPS and heart rate monitoring for up to 20 hours in Low Power Mode.*
Offline tasks continue without Wi-Fi or cellular
Apple lists workout and activity tracking, alarms and timers, Apple Pay, heart-rate and other health functions, Compass, and playback of music, podcasts or audiobooks downloaded to the watch among functions available while disconnected. Exact availability varies by model and region. Prepare audio before leaving, and check that it is stored on the watch rather than merely available to stream.
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Clear out junk files and repair common Windows errorsFree Scan →Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Offline maps are available on supported models, but Apple requires a compatible paired iPhone and software for setup; country availability also varies. Confirm the current requirements in Apple’s offline maps guidance before relying on a route.
Rank #3
![Apple Watch Ultra 3 [GPS + Cellular 49mm] Running & Multisport Smartwatch w/Rugged Titanium Case w/Anchor Blue Ocean Band. Satellite Communications, Advanced Health & Fitness Tracking](https://m.media-amazon.com/images/I/410UsX8rgRL._SL160_.jpg)
- RUGGED AND READY TO GO—The ultimate sports and adventure smartwatch is built to last with an extremely tough titanium case and a strong sapphire crystal display. Water resistant up to 100m—it’s great for swimmers, divers, and fans of high-speed water sports.*
- A FULL-FEATURED HEALTH TRACKER—Ultra 3 can take an ECG* and check your heart rhythm for signs of AFib—right from your wrist. The smartwatch sends alerts for possible hypertension,* an irregular heart rhythm,* or an unusually high or low heart rate. You can view your overnight health tracking metrics with the Vitals app,* track your sleep score, and take readings of your blood oxygen.*
- ULTIMATE RUNNING AND WORKOUT COMPANION—A superior fitness tracker for marathoners, triathletes, mountain bikers, backcountry hikers, and mountain climbers, Ultra 3 provides precision dual-frequency GPS, Pacer, Heart Rate Zones, Custom Workouts, running power, Workout Buddy powered by Apple Intelligence from your nearby iPhone,* training load, and more.
- KEEP HELP CLOSE AT HAND—Ultra 3 is a smartwatch that can detect a hard fall or severe car crash* and automatically help connect you to emergency services and notify your emergency contacts. Check In can automatically notify a loved one when you’ve arrived at your destination.
- MULTIDAY BATTERY LIFE—Ultra 3 is a smartwatch that’s engineered to give you even longer battery life. It’s perfect for trail runners—with up to 42 hours of normal use and up to 72 hours in Low Power Mode.* Track a workout with full GPS and heart rate monitoring for up to 20 hours in Low Power Mode.*
Satellite is for supported communications, not general data
Supported Ultra models can use satellite for specified emergency services, messaging and location sharing in supported locations. This is not a substitute for ordinary cellular data or unrestricted internet access. Regional and plan conditions apply, and a clear view of the sky may be needed. Review Apple’s current Ultra satellite guidance and follow its setup and connection instructions.
Garmin fēnix 9 Pro: distinguish inReach from other versions
LTE and satellite require the inReach version and an active plan
Garmin announced fēnix 9 and fēnix 9 Pro in August 2026. The fēnix 9 Pro inReach version adds built-in LTE and satellite connectivity for supported voice, text and SOS communications. Phone-free connectivity depends on an active inReach plan and service coverage; check the exact variant and local requirements before buying or setting out. Garmin’s fēnix 9 Pro inReach requirements describe supported features and service conditions.
Rank #4
![Apple Watch Ultra 3 [GPS + Cellular, 49mm] Black Titanium Case with Black Ocean Band (Renewed)](https://m.media-amazon.com/images/I/41pgd6Mf8nL._SL160_.jpg)
- Snowboarding, skiing, mountain biking, rowing, and more — you’ll find tons of additional ways to take your favorite sports and activities to the next level with Ultra 3 in the App Store. Tap in. Max out.
Satellite use requires a deliberate connection process
Garmin says its smartwatch satellite connection uses geostationary satellites. Stop moving and follow the on-screen steps to establish a connection. Garmin notes that this method differs from its handheld inReach products, and that connected features have limitations. Do not assume every function available through a phone connection or LTE is also available by satellite. Check Garmin’s fēnix 9 Pro inReach feature information for the current limits and coverage.
Use the manual’s connection modes to check individual features
The fēnix 9 owner manual separates features available through a phone connection, LTE and satellite. Check the mode listed for the specific feature you need rather than treating them as interchangeable. Garmin describes onboard storage and phone-free music through supported services; some music services require their own subscriptions. The fēnix 9 owner manual and product listing provide the relevant feature details.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Choose based on the connection and functions you need
| Need | Apple Watch Ultra 4 | Garmin fēnix 9 Pro inReach |
|---|---|---|
| Cellular connection away from the phone | GPS + Cellular version and an active plan from a supported carrier; availability and terms vary by region. Apple carrier information. | inReach version, active inReach plan and LTE coverage. Garmin requirements. |
| Communication outside cellular coverage | Supported satellite features for emergency services, messaging and location sharing, subject to location, plan and environmental conditions. Apple satellite guidance. | Supported inReach satellite features, subject to coverage and feature limits; use the on-screen connection process. Garmin feature information. |
| Tasks without any network | Workout and health functions, Apple Pay and audio downloaded to the watch; details vary by model and region. Apple’s disconnected-use guide. | Use the manual’s mode-by-mode feature list to distinguish onboard functions from LTE or satellite communications. Garmin owner manual. |
| Preparation before leaving | Arrange cellular service or confirm Wi-Fi access as needed; download audio and configure supported offline maps. | Activate the service, verify coverage and prepare maps and music as applicable. |
| Ongoing service | A carrier plan may be required for cellular functions; carrier terms vary. | An active inReach plan is required for connected functions; terms vary. |
These are manufacturer-described capabilities, not independent head-to-head reliability results. Your region, carrier, route, desired safety functions and willingness to pay for recurring service are the practical deciding factors.
Before you leave your phone behind
- Check the exact watch version. Confirm GPS + Cellular for Apple or inReach for Garmin; similarly named versions may not have the same connectivity.
- Activate the required service. Verify carrier support and plan terms for Apple, or the active inReach plan and coverage for Garmin.
- Prepare offline content. Download audio and configure maps where supported; do not assume streaming or online map data will work without a connection.
- Check the route and connection mode. Confirm local cellular, Wi-Fi or satellite availability and consult the manufacturer’s current feature guidance for any safety function you plan to use.
- Test the setup before departure. Try the relevant call, message, map or audio feature away from the phone while still somewhere you can troubleshoot.
What battery claims can—and cannot—tell you
Apple says Ultra 4 can track outdoor workouts for up to 45 hours. That is Apple’s manufacturer claim based on testing with preproduction hardware, not an independent comparison; Apple says battery life varies with use, settings, network and other factors. The announcement also gives a 50-hour multiday test scenario with specified checks, notifications, app use, workouts, music, sleep tracking and a stated mix of cellular and iPhone connection. Neither figure guarantees runtime for every phone-free outing. See Apple’s full test conditions.
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