Comparison

DiagonalOBDII vs Torque OBD2 Pro

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

Head to head
About

DiagonalOBDII

This app helps mechanics streamline vehicle drive cycles by providing live tracking of emissions monitors and diagnostic trouble codes. It offers precise guidance on drive cycle parameters and instant explanations for trouble codes, ensuring accurate diagnostics and faster vehicle readiness for inspection.

Highlights
  • Live drive cycle monitoring
  • Immediate DTC identification
  • Real-time monitor completion verification
  • Precise drive cycle parameter guidance
  • Professional, easy-to-navigate dashboard
  • Instant trouble code explanations
Read full description

Diagonal is designed specifically for mechanics who want to simplify and speed up vehicle drive cycles. Instantly track emissions monitors and diagnostic trouble codes (DTCs) live, ensuring accurate diagnostics and rapid vehicle readiness for inspection. Key Features: -Live Drive Cycle Monitoring: Clearly see the real-time status of emissions monitors as they run, complete, or require further action during your drive. -Immediate Diagnostics: Quickly identify and address active trouble codes (DTCs) as they appear, eliminating uncertainty during drive cycles. -Efficiency and Accuracy: Avoid unnecessary repeat drive cycles by verifying real-time monitor completion, ensuring vehicles pass inspection on the first try. -Precise Drive Cycle Guidance: Monitor essential drive cycle parameters such as speed, RPM, engine temperature, and throttle position to meet exact diagnostic requirements. -Professional Dashboard: Access all critical information quickly through a clear, easy-to-navigate interface tailored for automotive professionals. -Instant Code Explanations: Quickly interpret trouble codes with straightforward, mechanic-friendly explanations. Why Mechanics Trust Diagonal: -Saves Valuable Time: Complete diagnostic drive cycles accurately the first time. -Faster Inspections: Immediately identify vehicle readiness to streamline your workflow. -Reduces Diagnostic Uncertainty: Clear, actionable data presented in real-time. -Diagonal empowers professional technicians with the tools to perform diagnostics faster and more efficiently than ever before. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://diagonal-d070c.web.app/privacy.html

About

Torque OBD2 Pro

Transform your phone into a smart car tool. Connect via Bluetooth to read error codes, monitor live data, and log maintenance. Stay organized and ensure road safety with this vehicle companion.

Highlights
  • Bluetooth OBD2 connection
  • Read diagnostic trouble codes
  • Monitor live vehicle data
  • Maintenance log and notes
  • Vehicle safety tracking
Features
Read full description

Turn your device into a smart vehicle companion. Easily connect via Bluetooth to check diagnostics, read error codes, and monitor live data in real time. Keep track of maintenance tasks, repairs, and important notes to stay organized and ensure safety on the road. Your subscription will be charged to your iTunes account at confirmation of purchase and will automatically renew (at the duration selected) unless auto-renew is turned off at least 24 hours before the end of the current period. Current subscription may not be cancelled during the active subscription period; however, you can manage your subscription and/or turn off auto-renewal by visiting your iTunes Account Settings after purchase. For Support: https://sites.google.com/view/ttv-app-center/support See our Terms of Service & Privacy Policy below: https://sites.google.com/view/ttv-app-center/term-of-service https://sites.google.com/view/ttv-app-center/privacy-policy

Screenshots

DiagonalOBDII4 screens
Torque OBD2 Pro4 screens

Verdict

The call

The clearest difference is rating: DiagonalOBDII at 5.0 against Torque OBD2 Pro's 4.0. DiagonalOBDII also leads on monetization model (freemium vs subscription). Torque OBD2 Pro's advantage is update cadence (daily vs every 2 weeks) and ratings volume (8 vs 1). 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. DiagonalOBDII sells 4 in-app purchases, starting at $12.99 per month and Torque OBD2 Pro sells 3 in-app purchases, starting at $4.99 per 7 days. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

DiagonalOBDII holds the better App Store score, 5.0 against 4.0. That said, the two scores are not equally well evidenced: Torque OBD2 Pro has 8 ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

DiagonalOBDII ships an update every 2 weeks, Torque OBD2 Pro daily. The most recent releases landed on November 4, 2026 and November 8, 2026 respectively.

Scorecard5 real differences · 5 level
DiagonalOBDII versus Torque OBD2 Pro: the parameters behind the verdict, then further details
ParameterDiagonalOBDIITorque OBD2 Pro
PriceFreeFree
Rating5.0 (1 ratings) — better4.0 (8 ratings)
Positive reviews0.0% of reviews—
Number of ratings18 — better
Update frequencyEvery 2 weeksDaily — better
AdsNoNo
In-app purchasesYesYes
MonetizationFreemium — betterSubscription
DevicesiPhoneiPhone
Requires iOS18.116.1 — better
Further details — not scored
Size24 MB6 MB
Age rating4+4+
DeveloperKyle LouderbackTran Thi Viet

Customer experience

DiagonalOBDII

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

Torque OBD2 Pro

All ratings3 ratings
Positive66.7%
Neutral0.0%
Negative33.3%

In-app purchases

4 purchases

DiagonalOBDII

Subscriptions4
  • Diagonal Premium Monthly$12.991 Month
  • Diagonal Premium Trial1 Month trial$12.991 Month
  • Shop Owner - Monthly$17.991 Month
Show 1 more
  • Diagonal Premium Yearly$99.991 Year
3 purchases

Torque OBD2 Pro

Subscriptions2
  • Torque Premium Weekly$4.997 Days
  • Torque Premium Monthly$9.991 Month
One-time1
  • Torque Premium Lifetime$49.99

Questions

Is DiagonalOBDII free?
DiagonalOBDII is free to download, with in-app purchases available.
Is Torque OBD2 Pro free?
Torque OBD2 Pro is free to download, with in-app purchases available.
Which has better reviews, DiagonalOBDII or Torque OBD2 Pro?
DiagonalOBDII is rated higher. DiagonalOBDII averages 5.0 out of 5 from 1 ratings, while Torque OBD2 Pro averages 4.0 from 8 ratings.
Do DiagonalOBDII or Torque OBD2 Pro have ads?
Neither DiagonalOBDII nor Torque OBD2 Pro shows ads.
Which is updated more often, DiagonalOBDII or Torque OBD2 Pro?
DiagonalOBDII ships an update every 2 weeks, and Torque OBD2 Pro daily. Most recently, DiagonalOBDII was updated on November 4, 2026 and Torque OBD2 Pro on November 8, 2026.

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