Name: Solar Truth
Author: Davide_La_Sala

Your sunlight. Your battery.

Solar watches are fascinating: a little sunlight on your wrist can help your battery last longer. But what does that solar intensity graph actually mean in everyday life? How much did your afternoon outdoors contribute? And how does a sunny weekend compare with a week spent mostly indoors?

Solar Truth grew out of that curiosity. The idea is simple: make solar exposure easier to understand by connecting your watch’s readings with an estimated battery benefit and extra runtime.
Whether you’re walking, hiking or simply spending more time outside, Solar Truth helps you explore the contribution of sunlight to your watch’s autonomy.

Three views, one clearer picture
• TODAY — See your estimated solar battery benefit and the extra runtime it represents.
• DETAILS — Explore your strongest solar reading, average positive solar intensity, time with sunlight and the first and last light readings of the day.
• HISTORY — Compare daily, weekly and monthly summaries, with up to 31 days of recorded history. 

Discover how your solar exposure changes with your routine.
Built around your own readings.

Solar Truth samples solar intensity, battery level and cable-charging status in the background approximately every five minutes. New installations start fresh with your own data, and your history builds as you wear your watch.

The app combines an exposure model with personal battery-drain calibration when enough suitable data is available. Cable charging is tracked separately so it can be distinguished from the estimated solar contribution.

No account or internet connection is required for normal operation. Readings and history are stored locally on your watch.

A little honesty about the numbers
The “Truth” in Solar Truth means being clear about what we can know. Battery benefit and extra runtime are estimates, not direct measurements of harvested electrical energy. The app uses the solar-intensity readings available to it rather than a measured wattage output.

Activities, watch settings, changing power consumption and battery-gauge behaviour can all affect the results. Think of Solar Truth as a way to understand patterns and explore solar benefit over time.
Allow at least two samples before expecting a daily estimate. Weekly and monthly views become more useful as your history grows.

Controls
UP/DOWN: switch views.
START on HISTORY: cycle through day, week and month.
START on other views: take a sample and refresh.
MENU: open diagnostics and actions.
BACK: return or exit.

Created by Davide La Sala. Independent app, not affiliated with or endorsed by Garmin.