# ThinkDiag+ vs KDIAG

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.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

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.

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

## The numbers

| Metric | ThinkDiag+ | KDIAG |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.5 (4.3K ratings)](https://appshunter.io/ios/app/thinkdiag-plus/id1483420979/reviews)** | [3.3 (20 ratings)](https://appshunter.io/ios/app/kdiag/id6450169808/reviews) |
| Number of ratings | **4.3K** | 20 |
| Positive reviews | **74.1% of reviews** | 30.8% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Fortnightly** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 539 MB | 74 MB |
| Requires iOS | **12.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [THINKCAR INC](https://appshunter.io/developer/1464847379) | [祖策 谢](https://appshunter.io/developer/983519195) |

## What reviewers say

### ThinkDiag+

[App page](https://appshunter.io/ios/app/thinkdiag-plus/id1483420979)

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:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

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

**What reviewers complain about**

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

**Reported bugs**

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

**Requested features**

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


### KDIAG

[App page](https://appshunter.io/ios/app/kdiag/id6450169808)

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:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked 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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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*