Google Play
Version 1.1.5 · 2026-08-28
No release notes were provided for this version.
Too little checked to say Store information only. We haven’t analysed this app or read its reviews yet.
Not yet tested.
The store currently lists version 1.1.5, updated 2026-08-28.






Store screenshots supplied by the developer.
Do your plants keep dying? You're not alone, and it's probably not your fault.
Most plants fail because of one problem: light. Too little and they slowly starve. Too much and they burn out. Blackthumb gives you a Light Score for every plant and location in your home so you finally know what's going on.
— LIGHT SCORE CALCULATOR
Stop guessing. Enter your light readings (in lux, fc, or PPFD) and Blackthumb calculates your plant's Daily Light Integral (DLI) — the actual amount of usable light it receives each day. See instantly whether your Monstera is getting enough light in that corner, or if your grow light is doing its job. Compare against your plant's ideal range and get a clear "too low / in range / too high" rating.
Track natural light and grow light separately. See a confidence score that improves as you log more readings. Powered by real plant science, not vague color zones.…
From the developer’s store description.
For developers and the curious
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Supporting measurements: not a complete list of possible harms or positives. Measurement vocabulary 1.4 · how these are measured
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