# KDIAG vs VDIAGTOOL

The clearest difference is rating: KDIAG at 3.3 against VDIAGTOOL's 2.8. VDIAGTOOL's advantage is review sentiment (40% vs 31%) and iOS requirement (15.6 vs 17.0). On price, ratings volume, update cadence and ads there is nothing between them.

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

KDIAG holds the better App Store score, 3.3 against 2.8. Both are backed by a comparable volume of ratings — 20 and 8 respectively. Written reviews complicate that: 31% of KDIAG's written reviews are positive against 40% of VDIAGTOOL's, so the app with the better star average is not the one people write more warmly about.

KDIAG ships an update fortnightly, VDIAGTOOL every 3 weeks. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | KDIAG | VDIAGTOOL |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.3 (20 ratings)](https://appshunter.io/ios/app/kdiag/id6450169808/reviews)** | [2.8 (8 ratings)](https://appshunter.io/ios/app/vdiagtool/id6751025207/reviews) |
| Number of ratings | **20** | 8 |
| Positive reviews | 30.8% of reviews | **40.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 3 weeks |
| Monetization | Free | Free |
| Size | 74 MB | 1.1 GB |
| Requires iOS | 17.0 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [祖策 谢](https://appshunter.io/developer/983519195) | [Shenzhen VDIAGTOOL Technology Co., Ltd](https://appshunter.io/developer/1833169281) |

## What reviewers say

### 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


### VDIAGTOOL

[App page](https://appshunter.io/ios/app/vdiagtool/id6751025207)

This app provides comprehensive vehicle diagnostics, acting as a portable, professional solution. It connects to a Bluetooth OBDII adapter for full-system scanning and special functions on various car brands.

**Highlights:** Full-system vehicle diagnostics, Professional special functions (oil reset, DPF regen, EPB), High-speed Bluetooth OBDII adapter included, Portable, pocket-sized design, Cross-platform iOS compatibility

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is KDIAG free?

KDIAG is free to download, with no in-app purchases.

### Is VDIAGTOOL free?

VDIAGTOOL is free to download, with no in-app purchases.

### Which has better reviews, KDIAG or VDIAGTOOL?

KDIAG is rated higher. KDIAG averages 3.3 out of 5 from 20 ratings, while VDIAGTOOL averages 2.8 from 8 ratings.

### Do KDIAG or VDIAGTOOL have ads?

Neither KDIAG nor VDIAGTOOL shows ads.

### Which is updated more often, KDIAG or VDIAGTOOL?

KDIAG ships an update fortnightly, and VDIAGTOOL every 3 weeks. Most recently, KDIAG was updated on October 24, 2026 and VDIAGTOOL on October 25, 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.*