Comparison

OBD2 Scanner | OBD Auto Doctor vs ThinkDiag+

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

Head to head
About

OBD2 Scanner | OBD Auto Doctor

Diagnose your car's engine light issues and monitor real-time performance data. This app allows you to read and clear diagnostic trouble codes, track fuel consumption, and view sensor data. It's a comprehensive tool for understanding your vehicle's health.

Highlights
  • Read and clear OBD2 diagnostic trouble codes (DTC)
  • Reset Check Engine Light
  • Monitor real-time vehicle data and sensor readings
  • Track fuel consumption
  • Read readiness monitor status for emissions testing
  • Initiate service routines
  • Send diagnostic data via email
Read full description

Turn your iPhone into a powerful OBD2 car scanner and diagnose your vehicle yourself. Check why your Check Engine Light is on, read and clear diagnostic trouble codes, monitor live engine data, and check emissions readiness — all from your iPhone or iPad with a compatible OBD2 dongle. CHECK YOUR CHECK ENGINE LIGHT Don't guess what's wrong with your car. OBD Auto Doctor reads diagnostic trouble codes from your vehicle and provides detailed information to help you understand what they mean. • Read diagnostic trouble codes (DTCs) • Clear Check Engine Light codes • View detailed code descriptions • Read freeze-frame data MONITOR YOUR CAR IN REAL TIME See what's happening while your engine is running with live OBD2 data. • Engine RPM and vehicle speed • Coolant temperature • Fuel system and fuel trim data • Throttle position • Intake air and engine load • Oxygen sensor data • And many other vehicle parameters Create your own dashboard and choose exactly which sensors you want to monitor. CHECK EMISSIONS READINESS Preparing for an emissions or vehicle inspection? Check your vehicle's readiness monitors and see whether your car's emissions systems have completed their tests. WORKS WITH OBD2 DONGLES Connect OBD Auto Doctor to your vehicle using a compatible Bluetooth, Wi-Fi or Bluetooth Low Energy (BLE) OBD2 dongle. Compatible dongles include many ELM327-based adapters, OBDLink, Vgate, Linker, Veepeak and other compatible OBD2 interfaces. Please note: An OBD2 dongle is required to connect the app to your vehicle. Dongle compatibility and available features depend on your vehicle. MORE THAN JUST A CODE READER OBD Auto Doctor gives you access to the information your car's onboard diagnostic system makes available. • Read vehicle information • Monitor fuel consumption • View and record live sensor data • Read diagnostic trouble codes • Clear diagnostic trouble codes • Check emissions readiness • View freeze-frame data • Monitor vehicle performance Whether you're trying to understand a Check Engine Light, preparing your car for inspection, monitoring your engine, or simply want to know more about your vehicle, OBD Auto Doctor puts professional-style OBD2 diagnostics in your pocket. Download OBD Auto Doctor and start diagnosing your car today. SUBSCRIPTION OBD Auto Doctor offers optional subscriptions that unlock additional features. Terms of Use: https://www.obdautodoctor.com/terms

About

ThinkDiag+

This app provides professional-level vehicle diagnostics, offering features like reading/clearing fault codes, data flow analysis, and special maintenance functions. It supports a wide range of car brands and allows users to subscribe to specific diagnostic software. Connects via Bluetooth to your smartphone for intelligent vehicle analysis.

Highlights
  • OE-level diagnostic functions
  • Full OBD II diagnosis
  • Special maintenance functions
  • Supports 100+ vehicle brands
  • Automatic VIN reading
  • Professional diagnostic reports
  • In-app user community
Features
Read full description

1. Profession functions refer to OE level functions, such as read/clear code, data flow diagram, read ECU, drive test, bidirectional special functions, etc. 2. Support full-function OBD II diagnosis, read data flow, freeze frame read IM/real-time data, read/clear fault code, vehicle on-board monitoring/computer system control operation and read vehicle information. 3. Support vehicle maintenance light return to normal. 4. Select any vehicle diagnostic software, covering up to 39 major automobile manufacturers. 5. Support automatic VIN reading and one-key diagnosis. 6. Clear interpretation of fault codes and generate professional diagnostic reports. 7. Be able to communicate with other users within the ThinkDiag community (share/help/support). Not only for "ThinkDiag" and "ThinkDiag 2" device, but also works for "ThinkDiag Mini", "ThinkDirver", and "Thinkcar Pro" devices. ThinkDiag, an innovative vehicle diagnostic tool, is specially designed for repair technicians, small and medium-sized repair shops, and DIYers, to achieve the original manufacturer level diagnostic performance. It supports more than 100 vehicle brands of diagnostic services, including 15 special maintenance reset functions. ThinkDiag is as good as those comprehensive diagnostic equipment costed thousands of dollars. ThinkDiag is also an intelligent diagnostic device. Connecting with smartphone via Bluetooth, it is controlled to work by app. In the app, there is a diagnostic software store, and users can subscribe for diagnostic software according to their needs. ***Contact Us W: www.mythinkcar.com E: service@mythinkcar.com P: +1 833-692-2766 2151 S Haven Ave Unit 203 Ontario CA 91761 USA

Screenshots

OBD2 Scanner | OBD Auto Doctor4 screens
ThinkDiag+4 screens

Verdict

The call

OBD2 Scanner | OBD Auto Doctor and ThinkDiag+ both sit at 4.4 stars, but that hides the real split: 74% of ThinkDiag+'s written reviews are positive against 30% of OBD2 Scanner | OBD Auto Doctor's. ThinkDiag+ also leads on in-app purchases (none vs 9) and iOS requirement (12.0 vs 17.0). On price, rating, ratings volume and update cadence 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. OBD2 Scanner | OBD Auto Doctor sells 9 in-app purchases, starting at $4.99 per month. ThinkDiag+ asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.4 for OBD2 Scanner | OBD Auto Doctor against 4.5 for ThinkDiag+. Both are backed by a comparable volume of ratings — 6.2K and 4.4K respectively. Written reviews are what separate them: 30% of OBD2 Scanner | OBD Auto Doctor's written reviews are positive against 74% of ThinkDiag+'s.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 weeks. The most recent releases landed on November 1, 2026 and November 2, 2026 respectively.

Scorecard3 real differences · 7 level
OBD2 Scanner | OBD Auto Doctor versus ThinkDiag+: the parameters behind the verdict, then further details
ParameterOBD2 Scanner | OBD Auto DoctorThinkDiag+
PriceFreeFree
Rating4.4 (6.2K ratings)4.5 (4.4K ratings) — better
Positive reviews30.3% of reviews73.8% of reviews — better
Number of ratings6.2K — better4.4K
Update frequencyEvery 3 weeksEvery 3 weeks
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.012.0 — better
Further details — not scored
Size19 MB539 MB
Age rating4+17+
DeveloperCreosysTHINKCAR INC

Customer experience

OBD2 Scanner | OBD Auto Doctor

All ratings6,206 ratings
Positive84.4%
Neutral4.1%
Negative11.5%
Written reviews577 reviews
Positive30.3%
Neutral8.3%
Negative61.4%

ThinkDiag+

All ratings4,308 ratings
Positive88.1%
Neutral2.7%
Negative9.2%
Written reviews282 reviews
Positive73.8%
Neutral2.5%
Negative23.8%

User reviews

OBD2 Scanner | OBD Auto Doctor

From 6.2K App Store ratings

What we love

  • 🚀 Works great
  • 👍 Easy to use
  • 🚀 Accurate diagnostics
  • 🚀 Extensive adapter support
  • 👍 Helpful for DIY mechanics

Room to improve

  • 🔒 Requires subscription for full functionality
  • 🐛 Connection issues
  • 🐛 Inconsistent performance
  • 🐛 Doesn't work with all vehicles
  • 💰 Expensive subscription

ThinkDiag+

From 4.4K App Store ratings

What we love

  • 🚀 Easy to use
  • 🚀 Powerful diagnostic capabilities
  • 🚀 Affordable price
  • 🚀 Helpful customer support
  • 🚀 Versatile for DIY and professionals

Room to improve

  • 🐛 Occasional crashes or freezes
  • 🐛 Compatibility issues with certain vehicles
  • 🔒 Concerns about annual subscription fees
  • 🔒 Limited functionality on iOS devices

Bugs and requests

OBD2 Scanner | OBD Auto Doctor

Reported bugs

4 issues
  • App crashes on launch
  • Fails to detect existing fault codes
  • Subscription issues and inability to cancel
  • Incompatible with certain OBD2 adapters

Requested features

6 requests
  • Add support for more vehicle makes and models
  • Improve Bluetooth/WiFi connectivity
  • Provide more detailed diagnostic information
  • Allow clearing of error codes without subscription
  • Add live data dashboards and graphs
Show 1 more
  • Integrate with vehicle maintenance scheduling

ThinkDiag+

Reported bugs

3 issues
  • Failure to recognize VIN or vehicle information
  • Inability to clear certain error codes
  • Inconsistent performance across different devices

Requested features

4 requests
  • Improved user interface and navigation
  • More detailed troubleshooting guides
  • Expanded vehicle coverage and special functions
  • Offline mode for diagnostics

In-app purchases

9 purchases

OBD2 Scanner | OBD Auto Doctor

Subscriptions8
  • Monthly (legacy)$4.991 Month
  • Personal, monthly$4.991 Month
  • Premium, monthly$5.991 Month
Show 5 more
  • Professional, monthly$6.991 Month
  • Yearly (legacy)$23.991 Year
  • Personal, yearly$23.991 Year
  • Professional, yearly$29.991 Year
  • Premium, annual3 Days trial$29.991 Year
One-time1
  • OBD Auto Doctor Pro (legacy)$29.99
None

ThinkDiag+

No in-app purchases

Questions

Is OBD2 Scanner | OBD Auto Doctor free?
OBD2 Scanner | OBD Auto Doctor is free to download, with in-app purchases available.
Is ThinkDiag+ free?
ThinkDiag+ is free to download, with no in-app purchases.
Which has better reviews, OBD2 Scanner | OBD Auto Doctor or ThinkDiag+?
ThinkDiag+ is rated higher. OBD2 Scanner | OBD Auto Doctor averages 4.4 out of 5 from 6.2K ratings, while ThinkDiag+ averages 4.5 from 4.4K ratings.
Do OBD2 Scanner | OBD Auto Doctor or ThinkDiag+ have ads?
Neither OBD2 Scanner | OBD Auto Doctor nor ThinkDiag+ shows ads.
Which is updated more often, OBD2 Scanner | OBD Auto Doctor or ThinkDiag+?
OBD2 Scanner | OBD Auto Doctor ships an update every 3 weeks, and ThinkDiag+ every 3 weeks. Most recently, OBD2 Scanner | OBD Auto Doctor was updated on November 1, 2026 and ThinkDiag+ on November 2, 2026.

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