# iHeatLoss vs CK

The clearest difference is price: CK at Free against iHeatLoss's $5.99. CK also leads on iOS requirement (9.0 vs 17.6). On update cadence, ads, in-app purchases and device support there is nothing between them.

CK is free to download; iHeatLoss costs $5.99 up front. Neither carries in-app purchases, so what you see is what you pay.

iHeatLoss ships an update every 12 months, CK every 16 months. The most recent releases landed on October 23, 2026 and October 27, 2026 respectively.

## The numbers

| Metric | iHeatLoss | CK |
| --- | --- | --- |
| Price | $5.99 | **Free** |
| Rating | **[1.0 (1 ratings)](https://appshunter.io/ios/app/iheatloss/id680564773/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 12 months** | Every 16 months |
| Monetization | Paid | — |
| Size | 9 MB | 25 MB |
| Requires iOS | 17.6 | **9.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Navtech Software](https://appshunter.io/developer/355517263) | [CARL KAMMERLING INTERNATIONAL LIMITED](https://appshunter.io/developer/1669128786) |

## What reviewers say

### iHeatLoss

[App page](https://appshunter.io/ios/app/iheatloss/id680564773)

This app assists plumbers and heating engineers in calculating the heat output needed for each room in a building. It accounts for fabric and ventilation heat loss, providing results in Watts and BTU to help select appropriate radiators. The app also tracks multiple rooms to estimate the total heating system requirement.

**Highlights:** Room-by-room heat loss calculation, Fabric and ventilation loss inclusion, Multiple room tracking, Watts and BTU output display, Reference data for temperature and air change, Total heating output estimation

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

**In-app purchases:** none


### CK

[App page](https://appshunter.io/ios/app/ck-tools/id1669128784)

**In-app purchases:** none


## Frequently asked questions

### Is iHeatLoss free?

iHeatLoss costs $5.99, with no in-app purchases.

### Is CK free?

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

### Do iHeatLoss or CK have ads?

Neither iHeatLoss nor CK shows ads.

### Which is updated more often, iHeatLoss or CK?

iHeatLoss ships an update every 12 months, and CK every 16 months. Most recently, iHeatLoss was updated on October 23, 2026 and CK on October 27, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*