Garmin-style solar smartwatch: Amazfit T-Rex Dual Solar with two displays or solar cells?

It now seems highly likely that Zepp Health is developing a smartwatch with solar charging capabilities, supported by a growing body of largely independent evidence. References to the feature have surfaced not only within the Zepp Health companion app but also in recent certification filings. Notably, these filings indicate that the device will launch under the name T-Rex Dual Solar. The moniker naturally invites speculation - though it should still be treated as such for now.

In theory, "Dual" could point to a dual-display setup. This approach is far from improbable: Garmin, for instance, pairs solar charging exclusively with Memory-in-Pixel (MIP) displays, as embedding solar cells beneath a bright AMOLED panel presents significant engineering hurdles. Technical constraints alone might compel the Amazfit T-Rex Dual Solar to feature two distinct screens. Beyond display-integration challenges, a dual-layer or hybrid setup makes practical sense for power efficiency: a low-power MIP panel could handle always-on timekeeping, while the power-hungry AMOLED display engages only for demanding tasks like navigation map rendering.

Alternatively, "Dual" could signal an entirely different hardware design. Uncovered parameters within the Zepp app reference watch_face_input_power and case_back_input_power. This suggests solar cells could be positioned on both the front and rear of the casing. While placing photovoltaic elements on the back might sound counterintuitive at first, it remains a feasible design choice. Depending on the chassis geometry, ambient light could still strike the outer edges of the underside while worn. Rear-mounted solar cells could also serve as a dedicated charging method when the watch is off the wrist - such as resting on a table during a break on a long hike.