Lux Light Meter - Luminance
Lux · EV · Modes · History
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Now with Outdoor, Indoor, and Photo modes. Track every reading with 7-day chart, calibrate, compare, share results as image, export CSV.
Lux Light Meter turns your iPhone into a precise illuminance meter with four purpose-built modes — and now keeps a full history of every reading you take.
FOUR MODES
• Auto — radial gauge with closest reference shown live.
• Outdoor — focused 0.001 to 100,000 lx with moonless night, twilight, overcast, full daylight, direct sun references.
• Indoor — focused 10 to 10,000 lx with corridor, living room, kitchen, office, reading desk, drafting, surgical references.
• Photo — EV @ ISO 100 readout plus suggested shutter speed at f/2.8.
WHAT'S NEW
• Measurement History — every reading is auto-saved with a 7-day trend chart and insights like "+12% vs your 7-day average".
• Notes & Favorites — add a note ("kitchen window 3pm") and star to any saved reading.
• Compare Mode — pick two saved readings and view the difference side by side.
• Calibration Offset — fine-tune your sensor in ±1 lx steps.
• Share Result — share your current lux as an image.
• CSV Export — share all your measurements as CSV for spreadsheets.
CORE FEATURES
• Precise ambient light measurement (lux)
• Kalman-smoothed sensor readings
• Min/Max/Avg tracking with elapsed time
• Log-scale range bar in Outdoor and Indoor modes
• EV exposure value for photographers
• Microphone calibration
FOR PHOTOGRAPHERS · INDOOR GARDENERS · ELECTRICIANS · STUDIO ENGINEERS · OFFICE ERGONOMICS · INDUSTRIAL DIAGNOSTICS
Available in 14 languages.
Ratings & Reviews
- New Camera Permission UX — clear guidance + Open Settings shortcut
- App state re-check (auto-detect when permission re-granted)
The developer, Kyu-Hee Jang, 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 Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
- Identifiers
- Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Identifiers
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Kyu-Hee Jang
- Size
- 51.8 MB
- Category
- Utilities
- Compatibility
Requires iOS 16.4 or later.
- iPhone
Requires iOS 16.4 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
18+
- 18+
- Contains
Advertising
- Copyright
- © Copyright 2026 Simon Jang. All rights reserved.