# 4 vs Evap Solutions

The clearest difference is in-app purchases: 4 at none against Evap Solutions's 2. 4 also leads on device support (3 vs 1) and iOS requirement (12.2 vs 17.6). Evap Solutions's advantage is update cadence (every 3 weeks vs every 7 months). On price and ads there is nothing between them.

Both are free to download. Evap Solutions sells 2 in-app purchases, starting at $9.99 per month. 4 asks for nothing beyond the download.

4 ships an update every 7 months, Evap Solutions every 3 weeks. The most recent releases landed on October 16, 2026 and October 18, 2026 respectively.

## The numbers

| Metric | 4 | Evap Solutions |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (2 ratings)](https://appshunter.io/ios/app/evap-solutions/id6754700234/reviews)** |
| Number of ratings | — | **2** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 3 weeks** |
| Monetization | — | Subscription |
| Size | 56 MB | 25 MB |
| Requires iOS | **12.2** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [Rural Computer Consultants, Inc.](https://appshunter.io/developer/640795441) | [1L Concrete Solutions](https://appshunter.io/developer/1849693371) |

## What reviewers say

### 4

[App page](https://appshunter.io/ios/app/4-t-propane-llc/id6469541309)

**Features:** macOS Compatibility

**In-app purchases:** none


### Evap Solutions

[App page](https://appshunter.io/ios/app/evap-solutions/id6754700234)

This app helps concrete professionals calculate evaporation rates based on weather conditions. It provides guidance to prevent cracks and improve concrete curing for stronger, longer-lasting results. A free trial is available before subscribing.

**Highlights:** Concrete evaporation rate calculation, Crack prevention guidance, Weather-based adjustments, User-friendly interface, Moisture control and curing management

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Subscription | $9.99 | per month |
| Annual Subscription | $39.99 | per year |


## Frequently asked questions

### Is 4 free?

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

### Is Evap Solutions free?

Evap Solutions is free to download, with in-app purchases available.

### Do 4 or Evap Solutions have ads?

Neither 4 nor Evap Solutions shows ads.

### Which is updated more often, 4 or Evap Solutions?

4 ships an update every 7 months, and Evap Solutions every 3 weeks. Most recently, 4 was updated on October 16, 2026 and Evap Solutions on October 18, 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.*