LumenLeaf: PPFD Grow Light
PAR DLI Meter for Houseplants
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Free PPFD, PAR & DLI meter for monstera, microgreens, herbs & hydroponics. No ads, no account, no subscription. Honest about camera vs. ALS accuracy.
LumenLeaf turns your phone into a real PAR / PPFD grow light meter for
monstera, fiddle leaf fig, pothos, snake plant, succulents, orchids,
microgreens, herbs, hydroponics, grow tents and legal home cultivation
— all free, offline, with no account, no ads, and no subscription.
Measure photosynthetically active radiation (PAR / PPFD), Daily Light
Integral (DLI), illuminance (lux / foot-candle) and color temperature
(Kelvin) directly with your phone's camera and ambient light sensor.
WHAT YOU CAN MEASURE
- PPFD in µmol/m²/s — real-time photon flux density
- DLI in mol/m²/d — daily light integral with photoperiod input
- Lux and foot-candle illuminance
- Color temperature in Kelvin (CCT)
- Per-light-source readings: Sunlight, White LED, HPS, CMH, Fluorescent, Mixed
WHY LUMENLEAF
- 100% free — every feature, every plant preset, no paywalls
- No account, no email, no sign-up
- Works fully offline
- Available in 20 languages from launch
- Honest about accuracy — we tell you when you're on camera mode vs ALS estimate
- No physical hardware to buy — interactive printer-paper diffuser walkthrough
- Zero data collection, no analytics SDK, no advertising IDs
PERFECT FOR
- Houseplant parents — monstera, fiddle leaf, pothos, snake plant, calathea, ZZ
- Microgreen growers
- Indoor herb gardens — basil, mint, rosemary, oregano
- Succulents, cacti and orchids
- Hydroponic and aeroponic setups
- Grow tent hobbyists
- Aquarium plant keepers (v1.1)
- Legal home cultivation
WHAT WE MEASURE THAT OTHER APPS HIDE
LumenLeaf is the only free grow light meter that openly distinguishes
camera-grade readings from ambient light sensor (ALS) estimates. If
your phone does not have a calibration profile, we tell you — no
silent fallback that quietly halves your accuracy.
HOW IT WORKS
LumenLeaf uses your phone's rear camera in RAW mode (when supported)
for research-grade illuminance, then converts to PPFD using
light-source-specific coefficients. On phones without RAW support,
we fall back to the ambient light sensor and clearly mark which mode
you are on. A simple printer-paper diffuser is required — build one
in under 2 minutes with our visual guide.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, lapnito.cz s.r.o., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- lapnito.cz s.r.o.
- Size
- 31.8 MB
- Category
- Utilities
- Compatibility
Requires iOS 14.0 or later.
- iPhone
Requires iOS 14.0 or later. - iPod touch
Requires iOS 14.0 or later. - Mac
Requires macOS 11.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 22 more
- English, Arabic, Czech, Danish, Dutch, French, German, Greek, Hindi, Indonesian, Italian, Japanese, Korean, Polish, Portuguese, Russian, Simplified Chinese, Spanish, Swedish, Thai, Turkish, Ukrainian, Vietnamese
- Age Rating
4+
- 4+
- Copyright
- Copyright © 2026 lapnito.cz s.r.o.