The Galaxy Watch Ultra is Samsung's first watch built without compromise for the top of the market: grade 4 titanium, a 590mAh battery rated for 100 hours in Power Saving mode, 10ATM water resistance, and an on-device Emergency Siren that operates with no phone and no network. It introduced the squircle case design that later spread to the standard Watch 8. Wear OS gives it no native iPhone connection - Merge builds one: pair Watch Ultra to your iPhone for notifications, call management, and Apple Health sync.
What Merge enables on Watch Ultra
After pairing, Merge connects Watch Ultra to your iPhone. Every iPhone notification arrives on the watch in real time - at 3,000 nits, the display is readable in direct sunlight without any wrist adjusting. You choose per app which alerts reach the watch, keeping the stream exactly as focused as you want. Alerts can be dismissed from the wrist.
Calls ring on the watch and can be answered and handled from your wrist - iPhone contacts sync to the watch so you see who's calling without touching the phone. Music on your iPhone is controllable from the watch: skip, pause, adjust volume mid-expedition. The Quick Button on the left side of the case can be mapped to launch music controls or any other function with a single press. In remote contexts where camera control matters, the watch acts as a remote shutter when the iPhone camera app is open.
Health data routes directly into Apple Health: heart rate, steps, distance, floors climbed, calories, and workouts with dual-frequency GPS routes and pace all sync automatically. Long-distance hikes, extended trail runs, and multi-hour rides land in the Health app with accurate routes and complete heart rate data. The 590mAh battery keeps continuous monitoring running for days without interruption.
On-watch features that run independently
AFib detection runs on the Watch Ultra itself. When an irregular rhythm is detected, the alert appears on the watch screen with no dependency on phone connectivity or Merge being active at that moment. Energy Score, Antioxidant Index, and Vascular Load are all visible in the Samsung Health watch app directly on the wrist - on-watch features that work regardless of whether the iPhone is nearby.
The Emergency Siren is hardware built into the Watch Ultra's case. In an emergency - injured on a trail, out of phone range, unable to use the watch screen - it triggers a 100dB alert from the wrist. No network, no phone, no Merge required. GPX route tracking and Track Back navigation are also fully on-device: load a route before heading out and the watch handles turn-by-turn navigation and return routing without a phone in your pocket.
First-time setup
Watch Ultra is designed to operate independently in demanding conditions, and the setup tools reflect that same independence - two complete paths, both capable of getting the watch fully initialized. The Galaxy Wearable app on Android is the preferred route: it handles Google account sign-in, Play Store configuration, and firmware updates together in one pass. If Android isn't available, the Merge iPhone app's built-in wireless installer handles standalone Watch Ultra activation from iPhone with no Android device required at any step.
Installing and pairing Merge
Keep iPhone and watch within a couple of feet of each other throughout.
- On your iPhone, search the App Store for Merge Watch and download it.
- On the Watch Ultra, open Play Store, search for Merge Watch, and install it.
- Launch Merge on your iPhone and keep it running in the foreground throughout.
- Open Merge on the Watch Ultra and accept Bluetooth access.
- When your iPhone appears on the watch screen, tap it to pair.
- Accept the OS Bluetooth pairing request when it appears on each device.
- Set up your Merge subscription via the iPhone app if prompted.
- Grant notification and health permissions on both devices when asked.
A watch built for reliability in the field should not have its connection quietly cut by a background task manager. Go to Settings - Battery - More battery settings - Sleeping apps on the watch and remove Merge from the list right after setup. Samsung's battery optimizer will otherwise treat Merge as an inactive background process and terminate it - exactly the kind of silent failure you don't want to discover mid-expedition.
Using Watch Ultra with an iPhone day to day
The Watch Ultra is the most capable Galaxy Watch for iPhone users who push into demanding environments. A 60-hour typical battery handles several days between charges; 100-hour Power Saving mode covers extended trips without power access. The Emergency Siren operates completely standalone - no phone, no network, no Merge required. Via Merge, the watch adds the full iPhone connection on top: notifications, calls, music control, camera remote, contacts, and complete health sync to Apple Health. It is the complete package.
