Comparison

ThinkDiag+ vs KDIAG

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

Head to head
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

About

KDIAG

This app offers comprehensive automotive fault detection and OBD functions for various car brands. It provides professional diagnostic services to quickly identify and resolve car issues, making driving safer and smoother for enthusiasts and professionals alike. The app supports 8 languages and is free to use.

Highlights
  • Comprehensive automotive fault detection
  • OBD functions
  • System fault diagnosis for mainstream brands
  • Free to use
  • Supports 8 languages
  • Professional diagnostic services
Features
Read full description

The "KDIAG" automotive diagnostic app will provide you with the most comprehensive automotive fault detection and OBD functions, supporting system fault diagnosis for various mainstream brand cars and providing free use. Whether you are a car enthusiast or a professional technician, you can easily use it. The app also supports 8 languages to meet the needs of users worldwide. The app provides professional automotive diagnostic services that can quickly identify and solve automotive faults. Whether you are at home or on the road, you can easily use our application to ensure that your car remains in optimal condition. Download and experience our car diagnostic app to make your driving safer and smoother! "KDIAG"汽车诊断APP将为您提供最全面的汽车故障检测和OBD功能,支持多种主流品牌汽车的系统故障诊断并免费提供使用,无论您是一位汽车爱好者或专业技师,都能轻松使用。App还支持8种语言,满足全球使用者的使用需求。App提供专业级的汽车诊断服务,能够快速识别和解决汽车故障。无论您是在家里还是在路上,都可以轻松使用我们的应用程式来确保您的汽车保持最佳状态。快来下载并体验我们的汽车诊断APP,让您的驾驶更加安全和顺畅!

Screenshots

ThinkDiag+4 screens
KDIAG4 screens

Verdict

The call

The clearest difference is review sentiment: ThinkDiag+ at 74% against KDIAG's 31%. ThinkDiag+ also leads on rating (4.5 vs 3.3) and ratings volume (4.3K vs 20). KDIAG's advantage is monetization model (free vs free with in-app purchases). On price, update cadence, ads and in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

ThinkDiag+ holds the better App Store score, 4.5 against 3.3. That said, the two scores are not equally well evidenced: ThinkDiag+ has 4.3K ratings behind it against 20, so its average is the more settled of the two. Written reviews point the same way: 74% of ThinkDiag+'s written reviews are positive against 31% of KDIAG's.

UpkeepUpdate frequency

ThinkDiag+ ships an update every 3 weeks, KDIAG fortnightly. The most recent releases landed on October 16, 2026 and October 8, 2026 respectively.

Scorecard5 real differences · 5 level
ThinkDiag+ versus KDIAG: the parameters behind the verdict, then further details
ParameterThinkDiag+KDIAG
PriceFreeFree
Rating4.5 (4.3K ratings) — better3.3 (20 ratings)
Positive reviews74.1% of reviews — better30.8% of reviews
Number of ratings4.3K — better20
Update frequencyEvery 3 weeksFortnightly — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS12.0 — better17.0
Further details — not scored
Size539 MB74 MB
Age rating17+4+
DeveloperTHINKCAR INC祖策 谢

Customer experience

ThinkDiag+

All ratings4,308 ratings
Positive88.1%
Neutral2.7%
Negative9.2%
Written reviews278 reviews
Positive74.1%
Neutral2.5%
Negative23.4%

KDIAG

All ratings20 ratings
Positive55.0%
Neutral10.0%
Negative35.0%
Written reviews13 reviews
Positive30.8%
Neutral23.1%
Negative46.2%

Bugs and requests

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

KDIAG

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

ThinkDiag+

No in-app purchases

None

KDIAG

No in-app purchases

Questions

Is ThinkDiag+ free?
ThinkDiag+ is free to download, with no in-app purchases.
Is KDIAG free?
KDIAG is free to download, with no in-app purchases.
Which has better reviews, ThinkDiag+ or KDIAG?
ThinkDiag+ is rated higher. ThinkDiag+ averages 4.5 out of 5 from 4.3K ratings, while KDIAG averages 3.3 from 20 ratings.
Do ThinkDiag+ or KDIAG have ads?
Neither ThinkDiag+ nor KDIAG shows ads.
Which is updated more often, ThinkDiag+ or KDIAG?
ThinkDiag+ ships an update every 3 weeks, and KDIAG fortnightly. Most recently, ThinkDiag+ was updated on October 16, 2026 and KDIAG on October 8, 2026.

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