J vs GAF QuickMeasure
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
J
Create, modify, and manage sheet metal profile designs for roofing, cladding, and general metal construction. This tool is tailored for professionals in the metal building industry.
- Sheet metal profile drawing
- Editing capabilities
- Project organization
- Roofing applications
- Cladding applications
- Metal building industry focus
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Drawing, editing, organizing of sheet metal profile projects. Profiles are used in roofing, cladding and general metal building industry.
GAF QuickMeasure
Generate comprehensive roof measurement reports quickly and accurately. Ideal for single-family homes with reports in under an hour, and commercial/multifamily properties within 24 hours. Reports include detailed measurements of roof area, pitch, and various components.
- Fast roof reports
- Accurate measurements
- Roof area calculation
- Pitch and component details
- Under 1-hour turnaround (single-family)
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GAF QuickMeasure™ delivers a complete roof measurement report guaranteed in under 1 hour for single family homes and in under 24 hours for commercial and multifamily properties! Starting at only $18 a report. Roof area, pitch, ridges, eaves, rakes, valleys, hips, flashing - all in under 1 hour.
Screenshots
Verdict
The clearest difference is rating: GAF QuickMeasure at 4.9 against J's 2.0. GAF QuickMeasure also leads on update cadence (monthly vs every 6 months) and ratings volume (997 vs 3). J's advantage is monetization model (free vs paid) and review sentiment (100% vs 83%). 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.
GAF QuickMeasure holds the better App Store score, 4.9 against 2.0. That said, the two scores are not equally well evidenced: GAF QuickMeasure has 997 ratings behind it against 3, so its average is the more settled of the two. Written reviews complicate that: 100% of J's written reviews are positive against 83% of GAF QuickMeasure's, so the app with the better star average is not the one people write more warmly about.
J ships an update every 6 months, GAF QuickMeasure monthly. The most recent releases landed on October 2, 2026 and October 18, 2026 respectively.
| Parameter | J | GAF QuickMeasure |
|---|---|---|
| Price | Free | Free |
| Rating | 2.0 (3 ratings) | 4.9 (997 ratings) — better |
| Positive reviews | 100.0% of reviews — better | 83.3% of reviews |
| Number of ratings | 3 | 997 — better |
| Update frequency | Every 6 months | Monthly — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free — better | Paid |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 11.0 — better | 16.0 |
| Further details — not scored | ||
| Size | 4 MB | 5 MB |
| Age rating | 4+ | 4+ |
| Developer | Jorns AG Lotzwil | GAF Corp. |
Customer experience
J
GAF QuickMeasure
Bugs and requests
J
Not enough reviews yet to summarise bugs or requests.
GAF QuickMeasure
Reported bugs
4 issues- Message code authentication not sending or timing out
- Order list error - 'orders not found' message causing app crashes
- App does not properly adjust layout for iPad and iPhone orientations
- App boots users out when encountering errors
Requested features
3 requests- Improved responsive design for tablets and mobile devices
- Better orientation handling for iPad and iPhone use
- Clearer disclosure of pricing and data collection policies during registration
In-app purchases
J
No in-app purchases
GAF QuickMeasure
No in-app purchases
