# RLM vs Sunny

The clearest difference is monetization model: RLM at free against Sunny's free with in-app purchases. RLM also leads on device support (3 vs 1) and iOS requirement (15.0 vs 17.6). Sunny's advantage is update cadence (weekly vs every 3 weeks). On price, rating, ratings volume and ads there is nothing between them.

Both are free to download. RLM sells 1 one-off in-app purchase and Sunny sells 3 in-app purchases, starting at $3.99 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 — 5.0 for RLM against 5.0 for Sunny. Both are backed by a comparable volume of ratings — 2 and 2 respectively.

RLM ships an update every 3 weeks, Sunny weekly. The most recent releases landed on November 3, 2026 and November 8, 2026 respectively.

## The numbers

| Metric | RLM | Sunny |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [5.0 (2 ratings)](https://appshunter.io/ios/app/rlm-flight/id6448285133/reviews) | [5.0 (2 ratings)](https://appshunter.io/ios/app/sunny-light-meter/id6781954982/reviews) |
| Number of ratings | 2 | 2 |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Weekly** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 6 MB | 11 MB |
| Requires iOS | **15.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [R.L.M. Software](https://appshunter.io/developer/289639238) | [Trevor Welsh](https://appshunter.io/developer/1629778950) |

## What reviewers say

### RLM

[App page](https://appshunter.io/ios/app/rlm-flight/id6448285133)

This aviation computer app offers a comprehensive suite of tools for pilots. It calculates various flight parameters, including altitude, airspeed, ground speed, wind components, and weight & balance. The app also features unit and currency conversions, making it a versatile utility for aviation professionals.

**Highlights:** Altitude & Cloud Base Calculations, Airspeed & Ground Speed Calculations, Wind Component & Correction Tools, Weight & Balance Calculations, Unit & Currency Conversion, Holding Pattern & Flight Plan Tools

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Lifetime Full Access | $9.99 | one-time |


### Sunny

[App page](https://appshunter.io/ios/app/sunny-light-meter/id6781954982)

This app helps film photographers achieve accurate exposures by providing real-time light metering. It offers multiple metering modes and customizable settings to match your camera and lenses, ensuring your shots are perfectly exposed.

**Highlights:** Four Exposure Modes (Av, Tv, A, M), Dual Metering Systems (Average, Spot), Gear Customization, Focal Length Matching, Save Settings (Exif Logger), Custom Metering Engine, Real-Time Feedback

**Features:** Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sunny Pro Monthly | $3.99 | per month |
| Sunny Pro Annual | $19.99 | per year |
| Sunny Pro Lifetime | $29.99 | one-time |


## Frequently asked questions

### Is RLM free?

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

### Is Sunny free?

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

### Which has better reviews, RLM or Sunny?

RLM and Sunny are both rated 5.0 out of 5 on the App Store, from 2 and 2 ratings respectively.

### Do RLM or Sunny have ads?

Neither RLM nor Sunny shows ads.

### Which is updated more often, RLM or Sunny?

RLM ships an update every 3 weeks, and Sunny weekly. Most recently, RLM was updated on November 3, 2026 and Sunny on November 8, 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.*