SSG On Site vs Stack Testers Friend
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
SSG On Site
Access crucial worksite information, including safety guidelines, contact details, and maps. Stay informed with the latest news and report accidents directly from your mobile device.
- Safety instructions
- Contact details
- Maps
- Latest news updates
- Accident alerts
Read full descriptionHide full description
SSG On Site holds important information about that the worksite wants you to know about. Here you will find safety instructions, contact details, maps etc. Keep yourself updated with the latest news that will be pushed to your mobile device. For your safety there is also the possibility to alert if the accident is there.
Stack Testers Friend
This mobile toolkit provides essential on-site calculations for stack testers. Quickly perform gas conversions, probe position calculations, and other vital engineering tasks without needing a laptop. It's designed for environmental engineers needing immediate access to data while working in the field.
- Gas conversion calculations
- Isokinetic sample position calculations
- Extraction rate calculations
- Gas density calculations
- Particulate matter normalization
- Calibration function calculations
Read full descriptionHide full description
The app has been developed by the Engineers of CES Environmental Instruments, one of the UKs leading environmental Test Houses and incorporates some of their on-site calculations in one easy to use app. When working on the stack and you need that quick answer to a gas conversion or probe position, the answer can be at your fingertips. Simple and easy to use the app contains lots of essential calculations for the stack tester without the need to manually calculate the value or start up a laptop. The app is an essential tool for the professional Environmental engineer having all the tools to quickly check the numbers whilst out and around site. The contents of the CES Environmental Instruments popular Engineers Note Book is preloaded within the app. The app can do the following and much more: - Calculate Dia, CSA, Circ. - Isokinetic sample positions, General & Tangential - Extraction rates - Gas density - Calculate H20 from wet & dry Oxygen - Gas ppm/mg/m³ conversions & Normalisation - LOD - Particulate Matter Normalisation & estimation of temp, H2O & O2 - Ranging & scaling of dust monitors & outputs - Calculation of values using calibration functions - Biomass fuels
Screenshots
Verdict
The clearest difference is review sentiment: Stack Testers Friend at 100% against SSG On Site's 50%. Stack Testers Friend also leads on device support (3 vs 1) and iOS requirement (13.0 vs 16.6). SSG On Site's advantage is update cadence (every 10 days vs every 7 months). On price, ads, in-app purchases and monetization model there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
SSG On Site ships an update every 10 days, Stack Testers Friend every 7 months. The most recent releases landed on October 17, 2026 and September 24, 2026 respectively.
| Parameter | SSG On Site | Stack Testers Friend |
|---|---|---|
| Price | Free | Free |
| Positive reviews | 50.0% of reviews | 100.0% of reviews — better |
| Update frequency | Every 10 days — better | Every 7 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone | iPhone, iPad, iPod — better |
| Requires iOS | 16.6 | 13.0 — better |
| Further details — not scored | ||
| Size | 109 MB | 33 MB |
| Age rating | 4+ | 4+ |
| Developer | SSG Standard Solutions Group AB | Lewis Holmes |
Customer experience
SSG On Site
Stack Testers Friend
In-app purchases
SSG On Site
No in-app purchases
Stack Testers Friend
No in-app purchases
Questions
Is SSG On Site free?
Is Stack Testers Friend free?
Do SSG On Site or Stack Testers Friend have ads?
Which is updated more often, SSG On Site or Stack Testers Friend?
Other comparisons
