# Photone - Grow Light Meter

> Perfectly light your plants!

Canonical page: [https://chrome-stats.com/d/id1450079523](https://chrome-stats.com/d/id1450079523)

## Overview

- **ID:** `id1450079523`
- **Platform:** Apple
- **Type:** Apple app
- **Status:** Available
- **Publisher:** Lightray Innovation GmbH
- **Category:** Utilities
- **Rating:** 4.60 / 5 (4,916 ratings)
- **Version:** 4.5.2
- **Last updated:** 2026-08-19
- **First published:** 2019-04-24
- **Size:** 80 MB
- **Data as of:** 2026-09-19
- **Store listing:** [Apple App Store](https://apps.apple.com/us/app/photone-grow-light-meter/id1450079523)
- **Website:** [https://growlightmeter.com](https://growlightmeter.com/)
- **Privacy policy:** [https://growlightmeter.com/privacy/](https://growlightmeter.com/privacy/)

## Description

Photone is a camera-based plant light meter that delivers research-grade accuracy for indoor growers. It measures PAR as PPFD, Daily Light Integral (DLI), illuminance in lux or foot-candles, and color temperature in kelvin, including extended PAR with ePPFD and eDLI. By processing RAW camera data and applying per-device calibration, Photone rivals professional PAR meters while remaining user-friendly and ad-free. A diffuser is required for accurate readings (you can DIY with printer paper or use the Diffuser Accessory). 

Upgrade options unlock premium features, in-app grow guides, and tools such as a plant light calculator. No ads or location permissions, and a commitment to sustainability through the developer's 1% for the Planet donations. Photone is optimized for grow tents, greenhouses, hydroponics, and other indoor setups, helping you optimize lighting for healthier plants.

## Rankings

- #26,327 — Overall

## Review summary

Reviewers largely praise the app for being easy to use and useful for measuring light for plants, especially with the diffuser accessory. However, consistent complaints focus on paywalls gating core features and the extra cost of a diffuser, plus notable accuracy and reliability concerns after updates. Several users feel misled about upfront pricing and would like built-in plant-light calculations. Overall, it’s helpful when it works, but the current monetization and reliability issues are major drawbacks.

### Pros

- Easy to use with an intuitive interface and straightforward lux mode switching.
- Helpful for ensuring plants receive the right amount of light and is used across grows.
- Diffuser accessory improves accuracy and speeds readings; many users consider it worth the cost when combined with the app.
- Able to measure lux from various light sources, supporting different setups.

### Cons

- Core functionality is paywalled; essential features require a subscription.
- Diffuser is required for accurate readings and is not clearly disclosed in the listing, adding extra cost.
- Accuracy and PPFD readings can become unreliable after updates, with reports of drift or incorrect numbers.
- Inability to test basic functionality before subscribing; perceived bait-and-switch and unmet expectations.
- Occasional reliability issues (crashes, readings disappearing) reported on some devices.

## Similar extensions and apps

- [GrowPAR](https://chrome-stats.com/d/id6762544264)
- [PPFD METER - Grow Light Meter](https://chrome-stats.com/d/id6479329051) — 4.60 / 5
- [Grow Light Meter: PPFD](https://chrome-stats.com/d/id6784830058)
- [Plant Light Meter: Lux & PPFD](https://chrome-stats.com/d/id1628111038) — 2.20 / 5
- [Par Meter : PPFD Monitor](https://chrome-stats.com/d/id6757111998) — 2.50 / 5
- [LumenLeaf: PPFD Grow Light](https://chrome-stats.com/d/id6771374329)
- [LightMeter Pro: Lux Meter](https://chrome-stats.com/d/id6759503979)
- [Light Meter Pro - Lux Measure](https://chrome-stats.com/d/id6777116706)
- [Lux Light Meter · Photometer](https://chrome-stats.com/d/id6759858193) — 4.80 / 5
- [MoeuPLTest](https://chrome-stats.com/d/id6757464940)
- [Light Meter For Plants](https://chrome-stats.com/d/id6755839439) — 3.30 / 5
- [Biotic Plant Light Meter](https://chrome-stats.com/d/id6795663857)

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Source: [Chrome-Stats](https://chrome-stats.com/d/id1450079523)