# VPD Chart vs PPFD METER

The clearest difference is ads: VPD Chart at none against PPFD METER's shown. VPD Chart also leads on review sentiment (74% vs 53%) and iOS requirement (15.1 vs 18.0). PPFD METER's advantage is ratings volume (118 vs 30). On price, rating, update cadence and in-app purchases there is nothing between them.

Both are free to download. VPD Chart sells 2 in-app purchases, starting at $3.99 per month and PPFD METER sells 3 in-app purchases, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 4.5 for VPD Chart against 4.6 for PPFD METER. Both are backed by a comparable volume of ratings — 30 and 118 respectively. Written reviews are what separate them: 74% of VPD Chart's written reviews are positive against 53% of PPFD METER's.

Both ship on a similar rhythm, roughly every 3 weeks. Both last shipped on September 22, 2026.

## The numbers

| Metric | VPD Chart | PPFD METER |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.5 (30 ratings)](https://appshunter.io/ios/app/vpd-chart/id6470015847/reviews) | **[4.6 (118 ratings)](https://appshunter.io/ios/app/ppfd-meter-grow-light-meter/id6479329051/reviews)** |
| Number of ratings | 30 | **118** |
| Positive reviews | **73.7% of reviews** | 52.6% of reviews |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 3 weeks | Every 3 weeks |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 49 MB | 43 MB |
| Requires iOS | **15.1** | 18.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [INNOVO DEV S.R.L.](https://appshunter.io/developer/1814828527) | [Candas Pamukcu](https://appshunter.io/developer/1735587895) |

## What reviewers say

### VPD Chart

[App page](https://appshunter.io/ios/app/vpd-chart/id6470015847)

This app calculates Vapor Pressure Deficit (VPD) using air temperature, relative humidity, and canopy temperature. It offers real-time charting, sensor integration, and educational tools to understand plant growth environments. Organize data by zones and visualize dew point areas.

**Highlights:** VPD calculation, Interactive VPD chart, Sensor integration, Zone organization, Dew point visualization, Grow Timeline

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| VPD Chart Plus (monthly) | $3.99 | per month |
| VPD Chart Plus (annual) | $29.99 | per year |


### 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 VPD Chart free?

VPD Chart is free to download, with in-app purchases available.

### Is PPFD METER free?

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

### Which has better reviews, VPD Chart or PPFD METER?

PPFD METER is rated higher. VPD Chart averages 4.5 out of 5 from 30 ratings, while PPFD METER averages 4.6 from 118 ratings.

### Do VPD Chart or PPFD METER have ads?

PPFD METER shows ads; VPD Chart does not.

### Which is updated more often, VPD Chart or PPFD METER?

VPD Chart ships an update every 3 weeks, and PPFD METER every 3 weeks. Most recently, VPD Chart was updated on September 22, 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.*