# Sign Drops vs VPD Chart

The clearest difference is price: VPD Chart at Free against Sign Drops's $1.99. VPD Chart also leads on update cadence (every 3 weeks vs every 7 months) and ratings volume (30 vs 1). Sign Drops's advantage is rating (5.0 vs 4.5) and in-app purchases (none vs 2). On ads there is nothing between them.

VPD Chart is free to download; Sign Drops costs $1.99 up front. VPD Chart sells 2 in-app purchases, starting at $3.99 per month. Sign Drops asks for nothing beyond the download.

Sign Drops holds the better App Store score, 5.0 against 4.5. That said, the two scores are not equally well evidenced: VPD Chart has 30 ratings behind it against 1, so its average is the more settled of the two.

Sign Drops ships an update every 7 months, VPD Chart every 3 weeks. The most recent releases landed on September 19, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | Sign Drops | VPD Chart |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/sign-drops/id1606554586/reviews)** | [4.5 (30 ratings)](https://appshunter.io/ios/app/vpd-chart/id6470015847/reviews) |
| Number of ratings | 1 | **30** |
| Positive reviews | — | 73.7% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 3 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Best chart rank | **#198** | — |
| Size | 21 MB | 49 MB |
| Requires iOS | 17.4 | **15.1** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Jeremy Barr](https://appshunter.io/developer/478732789) | [INNOVO DEV S.R.L.](https://appshunter.io/developer/1814828527) |

## What reviewers say

### Sign Drops

[App page](https://appshunter.io/ios/app/sign-drops/id1606554586)

**Currently charting:** #198 Top Paid · Utilities (US App Store)

Manage and track sign placements for events, yard sales, or campaigns. Record detailed notes and precise locations for each sign, and oversee multiple events simultaneously for efficient organization and retrieval.

**Highlights:** Intuitive sign tracking system, Detailed notes and precise locations, Multi-event management, Seamless sign retrieval, Maximizes visibility and impact

**In-app purchases:** none


### 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 |


## Frequently asked questions

### Is Sign Drops free?

Sign Drops costs $1.99, with no in-app purchases.

### Is VPD Chart free?

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

### Which has better reviews, Sign Drops or VPD Chart?

Sign Drops is rated higher. Sign Drops averages 5.0 out of 5 from 1 ratings, while VPD Chart averages 4.5 from 30 ratings.

### Do Sign Drops or VPD Chart have ads?

Neither Sign Drops nor VPD Chart shows ads.

### Which is updated more often, Sign Drops or VPD Chart?

Sign Drops ships an update every 7 months, and VPD Chart every 3 weeks. Most recently, Sign Drops was updated on September 19, 2026 and VPD Chart 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.*