# Lighting Calculations vs Stemly Convert

The clearest difference is price: Lighting Calculations at Free against Stemly Convert's $1.99. Lighting Calculations also leads on update cadence (every 5 weeks vs every 3 months) and iOS requirement (15.0 vs 17.6). Stemly Convert's advantage is in-app purchases (none vs 3) and ads (none vs shown). On device support there is nothing between them.

Lighting Calculations is free to download; Stemly Convert costs $1.99 up front. Lighting Calculations sells 3 in-app purchases, starting at $1.99 per 3 months. Stemly Convert asks for nothing beyond the download.

Lighting Calculations ships an update every 5 weeks, Stemly Convert every 3 months. The most recent releases landed on November 1, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | Lighting Calculations | Stemly Convert |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| Rating | **[4.8 (6 ratings)](https://appshunter.io/ios/app/lighting-calculations/id1021580336/reviews)** | — |
| Number of ratings | **6** | — |
| Positive reviews | 60.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 5 weeks** | Every 3 months |
| Monetization | Free with in-app purchases | — |
| Size | 33 MB | 1 MB |
| Requires iOS | **15.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Egal Net di Ettore Gallina](https://appshunter.io/developer/993232047) | [Andrzej Bandosz](https://appshunter.io/developer/1884301857) |

## What reviewers say

### Lighting Calculations

[App page](https://appshunter.io/ios/app/lighting-calculations/id1021580336)

This app transforms your smartphone into a comprehensive lighting design tool. It offers advanced calculations for room lighting, LED analysis, and efficiency, alongside quick conversions and essential technical resources. Ensure your lighting projects meet all standards and optimize energy usage.

**Highlights:** Room lighting design calculations, LED analysis (lifespan, photobiological risk), Energy efficiency calculations, Photometric code decoding, Lumen, Lux, Candela, Watt conversions, Normative requirements and technical guides, Light quality metrics (CRI, UGR)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PRO Version (3 months) | $1.99 | per 3 months |
| PRO Version (1 year) | $2.99 | per year |
| PRO Version (Lifetime) | $14.99 | one-time |


### Stemly Convert

[App page](https://appshunter.io/ios/app/stemly-convertaudio-converter/id6783737431)

**In-app purchases:** none


## Frequently asked questions

### Is Lighting Calculations free?

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

### Is Stemly Convert free?

Stemly Convert costs $1.99, with no in-app purchases.

### Do Lighting Calculations or Stemly Convert have ads?

Lighting Calculations shows ads; Stemly Convert does not.

### Which is updated more often, Lighting Calculations or Stemly Convert?

Lighting Calculations ships an update every 5 weeks, and Stemly Convert every 3 months. Most recently, Lighting Calculations was updated on November 1, 2026 and Stemly Convert on October 28, 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.*