Gas Checker vs CO2 Filter Calc
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Gas Checker
Streamline your gas and heating business with digital reporting and invoicing. Automate customer reminders, create PDF reports, and integrate with accounting software. Eliminate paper forms and manage all your job documentation efficiently.
- Create PDF reports (certificates, invoices, quotes)
- Automated customer reminders
- Digital job sheets
- Quickbooks/Xero integration
- Cloud data sync
- Eliminate paper forms
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No1 software for Gas Installers and Heating Engineers and Plumbers in the UK and Ireland. Save time and money and Create Gas Reports, Invoices, Quotes, Job sheets and many more PDF reports and revolutionise your business. Never lose a customer again and maximise your repeat business automatically. Create digital documents for all your Gas and Heating related work. Get automated reminders each year to boost your annual repeat income. say good bye to paper forever. Link your account to Quickbooks and Xero and be MTD compliant. Gas Checker allows you to save, email and print them, this means you never have to carry a paper certificate book ever again. We include the following certificates:- Domestic Gas Safety Certificate, Gas breakdown/Service Record, Gas Warning Notice, Gas Service/Maintenance Check List, Leisure Industry Gas Safety Certificate, LPG Gas Safety Record. The app has many powerful features, which will help you fill in the required certificate easily and smoothly, all data can then be synced to the WEB so you will never lose it. Possibly the most useful App a Gas Engineer could wish for. Twitter @gaschecker When Registering for the first time after install, please make sure of the following 1) Ensure your username does not have any spaces ie Gas Checker - it should be GASCHECKER 2) Depending on the file size of your image will depend on the time it takes to Register your device. The Device needs to contact the Gas Checker server, So please be patient we hope you find this information helpful
CO2 Filter Calc
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The TOMCO Systems Filter Calculator is an assistant tool for sizing CO2 Polishing Filters. This app will help you understand what size filter will be necessary for your system to ensure you get the best product. As the exclusive U.S. distributor of Sure Purity filters, TOMCO2 Systems is proud to offer Sure Purity's high-quality products that are trusted by some of the biggest names in the industry. Sure Purity manufactures an advanced range of carbon dioxide multi-barrier polishing filters – carbogaurd. These barrier filters offer 12-month maintenance intervals while simultaneously offering the most enhanced protection from Carbonyl Sulphide (COS).
Screenshots
Verdict
The clearest difference is update cadence: CO2 Filter Calc at weekly against Gas Checker's every 3 weeks. Gas Checker's advantage is iOS requirement (12.0 vs 14.0). On price, ads, in-app purchases and device support 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.
Gas Checker ships an update every 3 weeks, CO2 Filter Calc weekly. The most recent releases landed on November 1, 2026 and October 27, 2026 respectively.
| Parameter | Gas Checker | CO2 Filter Calc |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (1 ratings) — better | — |
| Positive reviews | 61.1% of reviews | — |
| Number of ratings | 1 — better | — |
| Update frequency | Every 3 weeks | Weekly — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 12.0 — better | 14.0 |
| Further details — not scored | ||
| Size | 234 MB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | GasSoft limited | TOMCO2 Systems Company |
Bugs and requests
Gas Checker
Reported bugs
28 issues- Forgotten login details lock out users
- Cannot open App on iPad with iOS 10.3
- App crashes instead of opening
- App crashes again after connecting to internet
- Cannot get past 'add a profile picture' screen
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- Cancel and close buttons do not work
- Imported data lacks names and addresses
- Faults since update, cannot use app
- Incorrect dates on certificates
- App is very slow since last update
- Software saves multiple identical contacts
- Desktop figures do not match app figures
- Software regularly gets corrupted files
- Saved contacts disappear from the app
- App crashes frequently while filling out jobs
- App freezes and becomes unresponsive
- Searching by name crashes the app
- PC main hub shows blank invoices with error.xero
- Emailing quotes or receipts to customers does not send
- App does not update each other's iPhone/iPad details
- Reinstalling app loses history of certificates
- App sometimes loses gas certificates
- Software constantly has glitches
- Last update ruined the app
- Useful features have disappeared or don't work
- Credit card payment facility only works with a specific company
- UI is clunky and non-intuitive
- The 'done' button in the top right appears to do nothing
Requested features
3 requests- New commercial forms
- Stock control bolt-on
- Improve breakdown repair paperwork length
CO2 Filter Calc
Not enough reviews yet to summarise bugs or requests.
In-app purchases
Gas Checker
No in-app purchases
CO2 Filter Calc
No in-app purchases
Questions
Is Gas Checker free?
Is CO2 Filter Calc free?
Do Gas Checker or CO2 Filter Calc have ads?
Which is updated more often, Gas Checker or CO2 Filter Calc?
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