Comparison

CarbonData vs Vision Express

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

CarbonData

This app streamlines the process of generating and issuing chimney-sweeping certificates. Personalize certificates with company details, customer information, and fault reports. Easily export completed certificates as PDFs via email, with options to attach photos and store copies locally.

Highlights
  • Personalized certificate generation
  • Customer contact integration
  • Fault reporting with traffic light system
  • Customer consent and signature capture
  • PDF certificate export via email
  • Local data storage
  • CSV data export
Features
Read full description

Please note: The ability to generate certificates can only be unlocked through a monthly subscription* CarbonData is an app specially designed by sweeps for sweeps. It’s the digital version of the chimney-sweeping certificate given out to customers once a job has been completed. With CarbonData, you can personalise your certificate with your company details, logo, signature and approved trade / association symbols in the ‘Settings’ section as soon as the app is installed (don’t worry, these can be changed later). The app itself is very easy to use. When creating a certificate, simply search the Contacts section on your device and it will instantly complete the customers’ details for you. Or, if you prefer, you can enter their details manually. CarbonData really does help make a sweep’s work less hassle. It allows you to document all aspects of the flue and appliance you have swept; list any faults using comment boxes and a robust traffic light system; whilst making it clearer for customers to understand all the relevant information and any issues found. You can track the progression of the certificate with the navigation dots at the base of the screen and check each section as it appears on the certificate. A handy visual checklist at the end of the process quickly reveals any unfilled sections. Plus, certificates can still be issued even if one or more sections are incomplete.  And there’s more. Before issuing a certificate, sweeps can obtain the customer’s consent to the status of the site, permission for any future contact, and get the client’s signature. There’s even an option to indicate if the client wasn’t present at the time the job was done.  The completed certificate can then be dated and supplied to the customer via the sweep’s email as a PDF file ready to send. Sweeps then have the option to attach more images to the email, so giving customers even more info.  In the event of poor mobile reception or Wi-Fi being unavailable at the time of issue, the email will remain in the ‘Outbox’ until you get better reception or Wi-Fi comes back on. Once sent, a copy is stored in your ‘Sent’ items, so you’ll have a reliable backup or duplicate. Certificates can be viewed, deleted, emailed or organised by date or name in the 'View Certificates’ section and data can be exported as a CSV format. Finally, CarbonData does not store any information on the Cloud. Everything is stored on your device. So your personal database remains exactly that - personal. Key benefits of CarbonData: • Easy to use • Environmentally-friendly • Export database as a CSV file • No need for cloud technology • Designed for use in any country • Create certificates wherever you are • Issue certificates with device email • Add accompanying photos with email • Keep certificates organised *An in-app purchase of £9.99 per month unlocks the ability to generate an unlimited number of certificates using the CarbonData app, so long as the subscription is active. Payment will be charged to iTunes Account at confirmation of purchase. Subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period. Account will be charged for renewal within 24-hours prior to the end of the current period, and identify the cost of the renewal. Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user’s Account Settings after purchase. For our terms and privacy policy see http://www.carbondata.software/privacy-policy/

About

Vision Express

This app connects businesses with locum professionals, allowing users to find and book available shifts. It also facilitates on-the-go invoicing and provides real-time notifications for relevant opportunities.

Highlights
  • Find locum shifts
  • Book locum days
  • Manage invoicing
  • Push notifications for new shifts
  • Apply for shifts
  • Real-time availability
Features
Read full description

Find locum shifts, book your locum days, and manage your invoicing on the go with the free Vision Express APP. Once installed you will get push notifications as they occur for the shifts that match your criteria. You simply click the apply button and it is first come first served so you won't be applying for shifts that are no longer available. Designed for Locum Optometrists and Contact Lens Opticians and all other supporting roles within Optics. This app is managed by LocumBell.

Screenshots

CarbonData4 screens
Vision Express4 screens

Verdict

The call

The clearest difference is review sentiment: CarbonData at 80% against Vision Express's 29%. Vision Express's advantage is in-app purchases (none vs 1) and update cadence (every 3 days vs monthly). On price, ads, device support and iOS requirement 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. CarbonData sells 1 in-app purchase, starting at $9.99 per month. Vision Express asks for nothing beyond the download.

UpkeepUpdate frequency

CarbonData ships an update monthly, Vision Express every 3 days. The most recent releases landed on October 3, 2026 and October 24, 2026 respectively.

Scorecard4 real differences · 6 level
CarbonData versus Vision Express: the parameters behind the verdict, then further details
ParameterCarbonDataVision Express
PriceFreeFree
Rating3.0 (1 ratings) — better—
Positive reviews80.0% of reviews — better28.6% of reviews
Number of ratings1 — better—
Update frequencyMonthlyEvery 3 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS12.012.0
Further details — not scored
Size41 MB13 MB
Age rating4+4+
DeveloperVandyke Consulting LTDLocumBell

Customer experience

CarbonData

All ratings1 ratings
Positive0.0%
Neutral100.0%
Negative0.0%
Written reviews5 reviews
Positive80.0%
Neutral20.0%
Negative0.0%

Vision Express

Written reviews28 reviews
Positive28.6%
Neutral7.1%
Negative64.3%

In-app purchases

1 purchases

CarbonData

Subscriptions1
  • Unlock the app$9.991 Month
None

Vision Express

No in-app purchases

Questions

Is CarbonData free?
CarbonData is free to download, with in-app purchases available.
Is Vision Express free?
Vision Express is free to download, with no in-app purchases.
Do CarbonData or Vision Express have ads?
Neither CarbonData nor Vision Express shows ads.
Which is updated more often, CarbonData or Vision Express?
CarbonData ships an update monthly, and Vision Express every 3 days. Most recently, CarbonData was updated on October 3, 2026 and Vision Express on October 24, 2026.

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