# ThinkCar Bay vs KDIAG

The clearest difference is update cadence: KDIAG at every 3 weeks against ThinkCar Bay's every 5 months. KDIAG also leads on ratings volume (17 vs 3). ThinkCar Bay's advantage is review sentiment (50% vs 33%) and iOS requirement (9.0 vs 17.0). On price, rating, 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.

On the App Store both sit at effectively the same score — 3.3 for ThinkCar Bay against 3.4 for KDIAG. That said, the two scores are not equally well evidenced: KDIAG has 17 ratings behind it against 3, so its average is the more settled of the two. Written reviews are what separate them: 50% of ThinkCar Bay's written reviews are positive against 33% of KDIAG's.

ThinkCar Bay ships an update every 5 months, KDIAG every 3 weeks. The most recent releases landed on July 19, 2026 and September 21, 2026 respectively.

## The numbers

| Metric | ThinkCar Bay | KDIAG |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.3 (3 ratings)](https://appshunter.io/ios/app/thinkcar-bay/id6444782891/reviews) | **[3.4 (17 ratings)](https://appshunter.io/ios/app/kdiag/id6450169808/reviews)** |
| Number of ratings | 3 | **17** |
| Positive reviews | **50.0% of reviews** | 33.3% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 3 weeks** |
| Monetization | Free | Free |
| Size | 215 MB | 74 MB |
| Requires iOS | **9.0** | 17.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 17+ | 4+ |
| Developer | [THINKCAR INC](https://appshunter.io/developer/1464847379) | [祖策 谢](https://appshunter.io/developer/983519195) |

## What reviewers say

### ThinkCar Bay

[App page](https://appshunter.io/ios/app/thinkcar-bay/id6444782891)

This service application supports THINKCAR automotive diagnostic products. It offers tutorials, case studies, after-sales service, and online viewing of diagnostic reports. Manage your products and get assistance with their use.

**Highlights:** Product tutorials, Case studies, After-sales service, User product management, Online diagnostic report viewing

**Features:** macOS Compatibility

**In-app purchases:** none


### 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 ThinkCar Bay free?

ThinkCar Bay 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, ThinkCar Bay or KDIAG?

KDIAG is rated higher. ThinkCar Bay averages 3.3 out of 5 from 3 ratings, while KDIAG averages 3.4 from 17 ratings.

### Do ThinkCar Bay or KDIAG have ads?

Neither ThinkCar Bay nor KDIAG shows ads.

### Which is updated more often, ThinkCar Bay or KDIAG?

ThinkCar Bay ships an update every 5 months, and KDIAG every 3 weeks. Most recently, ThinkCar Bay was updated on July 19, 2026 and KDIAG on September 21, 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.*