The best gas safety record (CP12) apps in the UK, compared for 2026
Our shortlist for 2026: Maintivo, Gas Engineer Software, Gas Certificate App by Trade Apps, Easy Safety Cert, iCertifi, Tradify and Commusoft. For pay as you go, Easy Safety Cert. For gas only, Gas Engineer Software or iCertifi. For gas plus F-Gas in one app, Maintivo. For a full office system, Tradify or Commusoft.
Published 28 September 2026. Reviewed by the Maintivo team.
A word before we start. We make Maintivo, so read this with that in mind. We have tried to be fair, we name who each app suits, and where another app is the better fit we say so.
One thing to clear up first. The document is officially the Landlord Gas Safety Record, set out in the Gas Safety (Installation and Use) Regulations 1998. "CP12" and "gas safety certificate" are the everyday names for it, and the first comes from the number of the old CORGI form. Whatever you call it, the Gas Safe registered engineer carries out the checks and signs it. An app only produces the record, sends it and stores it. Our plain-English guide to the CP12 covers the 12-month and 28-day rules.
The seven apps side by side
| App | Best for | CP12 on site | F-Gas | Offline | Invoicing | Price from |
|---|---|---|---|---|---|---|
| Maintivo | iPhone and iPad teams of 1 to 10, gas plus F-Gas | Yes | Yes, with CO₂e maths | Yes | Optional, £9.99 a month | £34.99 a month, 3-day trial, no contract |
| Gas Engineer Software | Sole traders to mid-size gas firms | Yes | No | Yes | On Core+ plan | About £18 per user a month, annual |
| Gas Certificate App (Trade Apps) | Gas engineers who want CP12 and invoicing together | Yes | Not stated | Not stated | Yes | About £20 per user a month |
| Easy Safety Cert (Ezicert) | Low-volume engineers, pay as you go | Yes | Not stated | Not stated | No | About £25 a year for 50 jobs |
| iCertifi (GasCert) | Apple-only gas engineers on a fixed price | Yes | No | Not stated | Not stated | £24.99 a month or £149 a year inc VAT |
| Tradify | Growing firms that want job management first | On a higher tier | Not ready, per their site | No | Yes | From £34 per user a month |
| Commusoft | Firms with 6 or more staff and an office team | Yes | Not stated | Not stated | Yes | Quote only, 12-month contract |
Prices are as published on each vendor's website in September 2026 and change; check before you decide. Other companies' names are their trademarks and we are not affiliated with them.
The seven apps, one by one
Maintivo
Maintivo is ours. It is an iPhone and iPad app for UK trade teams of 1 to 10. The Landlord Gas Safety Record form covers the premises, each appliance, the regulation 26(9) checks, combustion analysis, Benchmark commissioning and the warning notice. It also has Split AC/VRF and chiller F-Gas forms that work out tonnes of CO₂e and the next due date. Everything works offline, including photos and the signature, and a branded PDF goes to the landlord, agent or tenant on save. Engineers on a seat never see prices. Pro is £34.99 a month with a 3-day trial, seats from £8.99, invoicing £9.99, no contract. It does not do scheduling, dispatch or accounting, and there is no Android version. It suits a small gas and heating firm that also carries F-Gas. More on the gas engineer app page.
Gas Engineer Software
Gas Engineer Software is the long-standing gas-only choice. It is built around the CP12 and the other gas forms a sole trader or a mid-size firm uses every week. It works offline and the records are tidy. Invoicing is on the Core+ plan rather than the entry plan, so budget for that if you need it. There is no F-Gas form, so an engineer who also does air conditioning will need a second app. Pricing starts at about £18 per user per month on an annual plan, which is among the lowest here. It suits a gas engineer who does gas and nothing else and wants a mature, focused tool at a low monthly cost.
Gas Certificate App by Trade Apps
Trade Apps' Gas Certificate App covers the CP12 and the usual gas forms, with invoicing included rather than sold as an add-on. That is its main draw: one price, records and invoices together. F-Gas is not stated on their site, so ask before you rely on it. Offline use is not stated either, which is worth checking if you work below ground. Pricing is about £20 per user per month. It suits a gas engineer who wants the CP12 and invoicing in one place at a set per-user price, and who does not need F-Gas.
Easy Safety Cert (Ezicert)
Easy Safety Cert, also known as Ezicert, is the pay-as-you-go option. From about £25 a year for 50 jobs, it is the cheapest way on this list to produce a CP12 on a phone. There is no invoicing, and F-Gas and offline use are not stated. It suits a part-time or low-volume engineer who does a handful of gas safety records a month and does not want a monthly subscription. If you do more than a couple of jobs a week, the per-job model stops being cheap and a subscription is worth a look.
iCertifi (GasCert)
iCertifi, also sold as GasCert, is Apple only, like Maintivo. It produces the CP12 and the standard gas forms on iPhone and iPad. There is no F-Gas form. Pricing is £24.99 a month or £149 a year including VAT, and the annual plan works out noticeably cheaper. Offline use and invoicing are not stated on their site, so ask. It suits an iPhone-based gas engineer who wants a gas-only app at a fixed price and does not need F-Gas. Paying a year up front gets the better rate.
Tradify
Tradify is job management first. It does quotes, scheduling, dispatch, timesheets and invoicing, and the CP12 is available on a higher tier rather than the entry plan. Their site says F-Gas is not ready yet. It does not work offline, which matters in plant rooms and basements. Pricing starts from £34 per user per month, so the cost climbs with every engineer you add. It suits a growing firm that wants the whole office run from one system and has signal on most jobs. For that firm the CP12 is one form among many, not the main event.
Commusoft
Commusoft is built for firms with six or more staff. It is a full business platform with scheduling, dispatch, stock, CRM and invoicing, and the CP12 is in there alongside the rest. Pricing is quote only, on a 12-month contract. F-Gas and offline use are not stated on their site. It suits an established firm with an office team that wants everything in one system and is comfortable committing for a year. For a team of one to five it is more system, and more contract, than most need.
How do you choose?
Five questions sort most people. Answer them honestly and the list shortens itself.
Do you also do air conditioning or refrigeration?
If yes, this decides it. Maintivo is the only app here that states F-Gas leak-check forms with the CO₂e maths and next due date built in. Gas Engineer Software and iCertifi do not do F-Gas. Tradify says it is not ready. The rest do not state it. Any of those means a second app for the split systems. Details are on our F-Gas app page.
Do you need scheduling and dispatch?
If you have an office and a diary to run, look at Tradify or Commusoft. They are built for that, and the record forms come along with it. Maintivo, Gas Engineer Software, Trade Apps, Easy Safety Cert and iCertifi are record apps first. They will not run your diary, and you should not pay as if they did.
Do you work in basements and plant rooms with no signal?
Maintivo and Gas Engineer Software work fully offline. Tradify does not. The others do not state it, so ask them directly and test it in a real cellar during the trial. An app that greys out when the signal drops is an app you will end up finishing in the van.
Do you want engineers to see your prices?
If you use subcontractors or apprentices, this matters. In Maintivo, an engineer on a seat never sees prices or invoices, full stop. The full platforms handle it through role permissions, which work but need setting up. The gas-only apps vary, so check before you hand out logins.
Do you want a contract?
Commusoft is a 12-month commitment. Gas Engineer Software's lowest price is on an annual plan. iCertifi is cheaper paid yearly. Easy Safety Cert is paid per year of jobs. Maintivo is monthly through the App Store with no contract, no onboarding fee and no exit fee, and the pricing page has the full breakdown. Tradify is per user per month. None of these is wrong, but know which one you are signing up for.
Our honest summary
If you do gas only and count every pound, Gas Engineer Software or Easy Safety Cert. If you want the CP12 and invoicing in one fixed price, Trade Apps. If you are Apple only and gas only, iCertifi. If you need a dispatch board and have the staff to justify it, Tradify or Commusoft. If you are a team of one to ten that does gas and F-Gas, works offline, and wants no contract, that is what we built Maintivo's CP12 app for. The compare page goes deeper on the platform question.
£34.99 a month, no contract
Maintivo Pro is £34.99 a month for the owner or admin account, with a 3-day free trial charged through the App Store only if you keep it. Each engineer you add needs a seat from £8.99 a month, and invoicing is an optional £9.99 a month add-on. No minimum seat count and no exit fee.
Common questions
They are the same document. The official name under the Gas Safety (Installation and Use) Regulations 1998 is the Landlord Gas Safety Record. "Gas safety certificate" and "CP12" are the everyday names people use for it. CP12 comes from the number of the old CORGI form. Whatever you call it, it is a record of the checks a Gas Safe registered engineer carried out, and the engineer signs it.
We have not found a fully free CP12 app that stores your records and emails a PDF. Most offer a free trial or a pay-as-you-go price. Easy Safety Cert is the closest to free at about £25 a year for 50 jobs. Maintivo has a 3-day free trial, and nothing is charged if you cancel in your iPhone Settings at least 24 hours before it ends.
Yes. Every app on this list produces the Landlord Gas Safety Record on a phone, and most also on a tablet. You still carry out the checks yourself as the Gas Safe registered engineer, and you sign the record on the screen. The app fills in the form, builds the PDF and sends it.
Of the seven apps here, Maintivo is the only one that states F-Gas leak-check forms with the tonnes of CO₂e and next due date worked out for you. Gas Engineer Software and iCertifi do not do F-Gas. Tradify says on its site that F-Gas is not ready. Trade Apps, Easy Safety Cert and Commusoft do not state it.
No app makes a record valid. The record is valid because a Gas Safe registered engineer carried out the checks in the regulations and signed it. The app produces, sends and stores the record, and prints your registration number on it. Maintivo never certifies anything, and neither does any other app on this list.
Send the gas safety record before you leave
Three days free, no training day. Nothing is charged until the trial ends. Run a real visit through it and see.