# Mars Hydro vs PPFD METER

The clearest difference is rating: PPFD METER at 4.6 against Mars Hydro's 2.6. PPFD METER also leads on review sentiment (53% vs 24%) and ratings volume (118 vs 27). Mars Hydro's advantage is in-app purchases (none vs 3) and ads (none vs shown). On price, update cadence and device support there is nothing between them.

Both are free to download. PPFD METER sells 3 in-app purchases, starting at $1.99 per month. Mars Hydro asks for nothing beyond the download.

PPFD METER holds the better App Store score, 4.6 against 2.6. Both are backed by a comparable volume of ratings — 27 and 118 respectively. Written reviews point the same way: 24% of Mars Hydro's written reviews are positive against 53% of PPFD METER's.

Mars Hydro ships an update monthly, PPFD METER every 3 weeks. The most recent releases landed on August 11, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | Mars Hydro | PPFD METER |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.6 (27 ratings)](https://appshunter.io/ios/app/mars-hydro/id6479227564/reviews) | **[4.6 (118 ratings)](https://appshunter.io/ios/app/ppfd-meter-grow-light-meter/id6479329051/reviews)** |
| Number of ratings | 27 | **118** |
| Positive reviews | 23.8% of reviews | **52.6% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Monthly | **Every 3 weeks** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 45 MB | 43 MB |
| Requires iOS | **15.0** | 18.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [MARS TRADING RCC, INC.](https://appshunter.io/developer/1726858942) | [Candas Pamukcu](https://appshunter.io/developer/1735587895) |

## What reviewers say

### Mars Hydro

[App page](https://appshunter.io/ios/app/mars-hydro/id6479227564)

Control your smart grow system with this app. Manage LED lights, ventilation, and monitor environmental data like CO2, temperature, and humidity for optimal plant growth. Automate your entire grow kit to mimic natural conditions.

**Highlights:** LED light control with timers and simulation, Ventilation system management, Complete grow kit automation via iHub, Environmental data monitoring (CO2, temp, humidity, PPFD), Sunrise and sunset simulation

**In-app purchases:** none


### PPFD METER

[App page](https://appshunter.io/ios/app/ppfd-meter-grow-light-meter/id6479329051)

This app measures light intensity for plants, converting LUX to PPFD and DLI. It offers advanced light mapping, uniformity analysis, and efficiency insights to optimize plant growth. Customize profiles for different environments and growth stages.

**Highlights:** LUX, PPFD, DLI, and PAR measurements, Light mapping and distribution analysis, Uniformity and PPF evaluation, Energy efficiency and consumption tracking, Customizable setting profiles, Bluetooth sensor integration

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium | $1.99 | per month |
| Premium Plus | $2.99 | per month |
| Remove Ads | $29.99 | one-time |


## Frequently asked questions

### Is Mars Hydro free?

Mars Hydro is free to download, with no in-app purchases.

### Is PPFD METER free?

PPFD METER is free to download, with in-app purchases available.

### Which has better reviews, Mars Hydro or PPFD METER?

PPFD METER is rated higher. Mars Hydro averages 2.6 out of 5 from 27 ratings, while PPFD METER averages 4.6 from 118 ratings.

### Do Mars Hydro or PPFD METER have ads?

PPFD METER shows ads; Mars Hydro does not.

### Which is updated more often, Mars Hydro or PPFD METER?

Mars Hydro ships an update monthly, and PPFD METER every 3 weeks. Most recently, Mars Hydro was updated on August 11, 2026 and PPFD METER on September 22, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*