The Amazfit T Rex 3 is receiving firmware version 4.5.3.3, a small update package measuring about 11.77 MB. The release adds a new recreational diving workout along with offline route planning and several tweaks to navigation and underwater tracking.
Offline navigation gets a proper upgrade
The main news this time around is that Map app now supports offline route planning in two flavours. You can create a loop route or plot a point-to-point route from your current location to a chosen destination.
The more useful part is what happens when things go wrong mid-route. If you drift off course, the watch will automatically recalculate and get you back on track. That kind of auto-rerouting has been standard on dedicated GPS devices for years, so it is good to see it arrive here.
Diving gets some attention
Recreational diving joins the T-Rex 3’s workout library through Workout > More Workouts > Diving, sitting alongside the existing freediving modes rather than replacing them.
On that front, the depth algorithm for both Outdoor Freediving and Indoor Freediving has been optimised specifically for the moment you start a workout underwater.
BioCharge and stability improvements
Outside of the new activity mode and navigation tools the update includes a couple of smaller tweaks.
The BioCharge algorithm has been adjusted. BioCharge is Zepp Health’s energy style metric that estimates how much physiological energy the body has available during the day. Updates to this algorithm typically aim to make the metric react more realistically to sleep quality training load and recovery.
There is also a fix for a crash that could occur when viewing workout records from extremely long outdoor sessions. Ultra distance activities place unusual strain on logging systems because they produce very large datasets. The update addresses that issue which should help stability when reviewing those activities.
Taken together the update does not radically change what the Amazfit T Rex 3 can do but it does continue to refine the platform. Diving tracking becomes a little more complete and route navigation becomes more independent of the smartphone which suits the outdoor focus of the watch.
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