# Molnus vs Stair Calculator

The clearest difference is update cadence: Molnus at fortnightly against Stair Calculator's every 3 months. Molnus also leads on monetization model (free vs free with in-app purchases) and iOS requirement (13.0 vs 15.0). Stair Calculator's advantage is review sentiment (21% vs 13%). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Molnus sells 3 one-off in-app purchases and Stair Calculator sells 2 in-app purchases, starting at $9.99 per year. Whichever you choose, the download price is not the number that matters.

Molnus ships an update fortnightly, Stair Calculator every 3 months. The most recent releases landed on October 14, 2026 and October 19, 2026 respectively.

## The numbers

| Metric | Molnus | Stair Calculator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.1 (738 ratings)](https://appshunter.io/ios/app/stair-calculator-construction/id1493037366/reviews)** |
| Number of ratings | — | **738** |
| Positive reviews | 12.5% of reviews | **21.4% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 3 months |
| Monetization | **Free** | Free with in-app purchases |
| Size | 12 MB | 1 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [HJL IT & Development](https://appshunter.io/developer/1368468190) | [Phan Nhat Đang](https://appshunter.io/developer/1437390098) |

## What reviewers say

### Molnus

[App page](https://appshunter.io/ios/app/molnus/id1368468281)

Control and manage compatible cameras and their associated SIM cards. Receive instant notifications for events like image uploads and battery status, with secure cloud storage for your photos.

**Highlights:** Remote camera settings control, MolnusSIM card management, Event notifications (image upload, battery), Secure cloud storage, Wildlife detection, Photo gallery

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 100 Molnus Credits | $3.99 | one-time |
| 200 Molnus Credits | $7.99 | one-time |
| 500 Molnus Credits | $19.99 | one-time |


### Stair Calculator

[App page](https://appshunter.io/ios/app/stair-calculator-construction/id1493037366)

This app calculates essential parameters for stair construction, offering flexibility in input and providing multiple step set options. It supports various units and allows results to be easily copied.

**Highlights:** Calculate stair construction parameters, Flexible input for Run or Total Run, Determine largest and smallest step sets, Support for various units, Copy results to clipboard

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Annual Premium Package | $9.99 | per year |
| Unlock all features | $5.99 | one-time |

**What reviewers like**

- 👍 Easy to use
- 🚀 Helpful information
- 🚀 Provides useful calculations

**What reviewers complain about**

- 🐛 Doesn't work as expected
- 🔒 No way to cancel subscription
- 🔒 Difficult to cancel trial
- 🤬 Obnoxious ads
- 🤬 Misleading as a learning tool

**Reported bugs**

- Subscription numbers don't add up
- Doesn't provide promised features after purchase

**Requested features**

- Option to uninstall app
- Ability to calculate run based on rise and landing space
- Provide more detailed diagrams and visuals


## Frequently asked questions

### Is Molnus free?

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

### Is Stair Calculator free?

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

### Do Molnus or Stair Calculator have ads?

Neither Molnus nor Stair Calculator shows ads.

### Which is updated more often, Molnus or Stair Calculator?

Molnus ships an update fortnightly, and Stair Calculator every 3 months. Most recently, Molnus was updated on October 14, 2026 and Stair Calculator on October 19, 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.*