# Carista OBD2 vs ThinkDiag+

Carista OBD2 and ThinkDiag+ both sit at 4.6 stars, but that hides the real split: 74% of ThinkDiag+'s written reviews are positive against 34% of Carista OBD2's. ThinkDiag+ also leads on in-app purchases (none vs 14) and ads (none vs shown). Carista OBD2's advantage is chart position (#166 vs unranked). On price, rating, ratings volume and update cadence there is nothing between them.

Both are free to download. Carista OBD2 sells 6 in-app purchases, starting at $19.99 per month. ThinkDiag+ asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 4.6 for Carista OBD2 against 4.5 for ThinkDiag+. Both are backed by a comparable volume of ratings — 4.2K and 4.4K respectively. Written reviews are what separate them: 34% of Carista OBD2's written reviews are positive against 74% of ThinkDiag+'s.

Both ship on a similar rhythm, roughly every 3 weeks. Both last shipped on October 26, 2026.

## The numbers

| Metric | Carista OBD2 | ThinkDiag+ |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (4.2K ratings)](https://appshunter.io/ios/app/carista-obd2/id954363569/reviews)** | [4.5 (4.4K ratings)](https://appshunter.io/ios/app/thinkdiag-plus/id1483420979/reviews) |
| Number of ratings | 4.2K | **4.4K** |
| Positive reviews | 34.2% of reviews | **74.1% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 3 weeks | Every 3 weeks |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Best chart rank | **#166** | — |
| Size | 142 MB | 539 MB |
| Requires iOS | 16.4 | **12.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 17+ | 17+ |
| Developer | [Prizmos](https://appshunter.io/developer/954363568) | [THINKCAR INC](https://appshunter.io/developer/1464847379) |

## What reviewers say

### Carista OBD2

[App page](https://appshunter.io/ios/app/carista-obd2/id954363569)

**Currently charting:** #166 Top Grossing · Utilities (US App Store)

This app acts as a DIY car mechanic, allowing you to customize features, diagnose warning lights, monitor live data, and perform maintenance. Save time and money by handling common car tasks yourself.

**Highlights:** Customize car behavior and unlock hidden features, Diagnose and reset dashboard warning lights, Monitor real-time vehicle parameters, Perform simple DIY car maintenance procedures, Access advanced electronic diagnostics

**Features:** Vision Pro support

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Basic | $19.99 | per month |
| Pro | $19.99 | per month |
| 1 month Pro | $19.99 | per month |
| 3 month Pro | $29.99 | per 3 months |
| Pro | $59.99 | per year |
| One-Time Diagnostic & Reset | $9.99 | one-time |

**What reviewers like**

- 🚀 Easy to use
- 👍 Customization options
- 🚀 Efficient diagnostics
- 💡 Helpful for maintenance
- 👍 Great customer support

**What reviewers complain about**

- 💰 Expensive subscription
- 🔒 Requires account login
- 🐛 Connectivity issues
- 🔒 Locked features behind paywall
- 🐛 Unreliable functionality

**Reported bugs**

- App crashes and freezes
- Subscription issues and billing problems
- Incompatibility with certain OBD2 adapters
- Customization features not working as expected
- Inaccurate fault code detection

**Requested features**

- Support for more vehicle makes and models
- Offline diagnostics and customization
- Ability to save customization settings
- More detailed error code information
- Improved user interface and navigation


### 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


## Frequently asked questions

### Is Carista OBD2 free?

Carista OBD2 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, Carista OBD2 or ThinkDiag+?

Carista OBD2 is rated higher. Carista OBD2 averages 4.6 out of 5 from 4.2K ratings, while ThinkDiag+ averages 4.5 from 4.4K ratings.

### Do Carista OBD2 or ThinkDiag+ have ads?

Carista OBD2 shows ads; ThinkDiag+ does not.

### Which is updated more often, Carista OBD2 or ThinkDiag+?

Carista OBD2 ships an update every 3 weeks, and ThinkDiag+ every 3 weeks. Most recently, Carista OBD2 was updated on October 26, 2026 and ThinkDiag+ on October 26, 2026.

---

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