Finally, One Set of Numbers
Amazfit has added multi-device sync to its ecosystem, and it is long overdue. The new Multi-Device Activity Sync feature in Zepp OS 6 merges daily activity data across multiple Amazfit devices, keeping totals consistent for steps, calories, standing time, and distance. The feature is live on the Balance 3 and Balance Ultra, with more devices expected to follow.
This is the feature that Amazfit users have been asking for. People who run with one watch and wear another for sleep, or who switch between models depending on the workout, have been dealing with fragmented data for years. The Zepp app now pulls everything together so you see one set of numbers, not several conflicting ones.
How It Works
Multi-Device Activity Sync runs through the Zepp app, not device-to-device. That is the standard approach used across the industry, and it is the same architecture Garmin uses for TrueUp. When you have multiple Amazfit devices connected to the same Zepp account, the app merges the daily data and keeps totals consistent across both.
The synced metrics are steps, calories, standing, and distance. Zepp Health also mentions "other activity metrics" without being specific about what those cover. The feature works automatically once you have two devices linked to the same account.
Garmin Has Had This Since 2016
Amazfit is arriving late to this particular party. Garmin introduced TrueUp back in November 2016 and has been refining it ever since. By 2023, Garmin had extended the concept significantly with Unified Training Status, which added Primary Training Device and Primary Wearable designations to keep physiological metrics like VO2 max, training load, and recovery time consistent across the entire Garmin ecosystem.
Amazfit's first step is more modest. Multi-Device Activity Sync covers daily activity metrics, not training load or physiological data. The gap that matters most right now is HybridCharge. Amazfit's readiness score builds on biometric data plus user-reported context like stress, illness, and RPE. If a workout on a Helio Strap does not feed into the HybridCharge score on your Balance 3, the readiness metric is incomplete.
Zepp Health has not confirmed whether training load, recovery time, or HybridCharge scores cross device boundaries. Garmin closed that gap in 2018, two years after launching the basic sync. Amazfit has some work to do if it wants to match Garmin's depth here.
What Else Zepp OS 6 Brings
Multi-Device Activity Sync is the standout new feature, but Zepp OS 6 adds several other tools worth noting.
Daily Briefing builds on the old Morning Update and now covers both ends of the day. Morning briefings show weather, sleep data, your schedule, and training insights. Evening briefings look back at workouts, activity, and key health trends.
HybridCharge replaces BioCharge as the primary readiness score. It adds LifeLoad, which lets users log stress, illness, alcohol, physical strain, travel, and jet lag. RPE logging is also built in, so you can record how hard a workout felt after you finish. Boundary reminders can now trigger during workouts when HybridCharge is low, turning recovery from a morning score into an ongoing guide.
Training Calendar puts planned workouts and past sessions in one place, with support for Zepp Training, custom templates, and third-party plans. There is also a Training Library with Zepp courses available directly on the watch.
HYROX support includes training templates and Virtual Pace with stage guidance, target progress, and next-up previews. That aligns with the Balance 3 range's focus on hybrid fitness.
Navigation improvements bring Route Progress showing remaining distance, ascent, and descent to the next waypoint and final destination. Elevation Chart gives a clearer route profile view.
Launcher redesign puts the watch face at the center of navigation. Swipe right for workouts, swipe left for apps, swipe down for notifications, swipe up for Shortcut Cards. Physical buttons get a bigger role, which matters for gym use when touchscreens are unreliable.
The Bottom Line
Amazfit has finally answered Garmin TrueUp. Multi-Device Activity Sync is a genuine quality-of-life improvement for anyone using more than one Amazfit device. The sync architecture is right, the metrics are useful, and it makes the ecosystem feel less fragmented.
The gap is depth. Garmin has spent seven years building out its multi-device ecosystem, and Amazfit is at the starting line. HybridCharge is the obvious missing piece. If your readiness score cannot see workouts logged on a Helio Strap or a secondary watch, it is not giving you the full picture.
That said, Amazfit has moved quickly on features before. This is a real first step, and it is in the right direction.