# OBDSTAR vs simos.app

The clearest difference is rating: simos.app at 5.0 against OBDSTAR's 1.5. simos.app also leads on ads (none vs shown) and update cadence (every 4 days vs every 6 months). OBDSTAR's advantage is device support (3 vs 1) and iOS requirement (15.5 vs 17.6). On price, ratings volume 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.

simos.app holds the better App Store score, 5.0 against 1.5. Both are backed by a comparable volume of ratings — 4 and 2 respectively.

OBDSTAR ships an update every 6 months, simos.app every 4 days. The most recent releases landed on October 9, 2026 and October 1, 2026 respectively.

## The numbers

| Metric | OBDSTAR | simos.app |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [1.5 (4 ratings)](https://appshunter.io/ios/app/obdstar/id6447170127/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/simosapp/id6760018423/reviews)** |
| Number of ratings | **4** | 2 |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 6 months | **Every 4 days** |
| Monetization | Ad-supported | **Free** |
| Size | 122 MB | 6 MB |
| Requires iOS | **15.5** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 17+ | 4+ |
| Developer | [深圳市轩宇车鼎科技有限公司](https://appshunter.io/developer/1680461221) | [Tycho Sebastian Holzer](https://appshunter.io/developer/1882338941) |

## What reviewers say

### OBDSTAR

[App page](https://appshunter.io/ios/app/obdstar/id6447170127)

A handheld maintenance database for technicians, offering technical support, data queries, video viewing, and after-sales consultation. It provides a comprehensive database for automotive, motorcycle, and marine maintenance, aiming for efficient and professional service.

**Highlights:** Handheld maintenance database, Technical support, Data query, Video viewing, After-sales consultation, Comprehensive maintenance data

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

**In-app purchases:** none


### simos.app

[App page](https://appshunter.io/ios/app/simosapp/id6760018423)

This tool provides diagnostic, data logging, and flashing capabilities for VAG petrol engines with specific Simos ECUs. Monitor real-time engine parameters, analyze recorded sessions with graphs, and update your ECU with stock or custom tunes.

**Highlights:** Real-time ECU parameter monitoring, Live data logging via Bluetooth LE, ECU identification (software/calibration IDs), Multi-channel graph analysis of logged sessions, ECU and TCU flashing (stock and custom tunes), Support for Simos 18.x and 12.1 ECUs

**In-app purchases:** none


## Frequently asked questions

### Is OBDSTAR free?

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

### Is simos.app free?

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

### Which has better reviews, OBDSTAR or simos.app?

simos.app is rated higher. OBDSTAR averages 1.5 out of 5 from 4 ratings, while simos.app averages 5.0 from 2 ratings.

### Do OBDSTAR or simos.app have ads?

OBDSTAR shows ads; simos.app does not.

### Which is updated more often, OBDSTAR or simos.app?

OBDSTAR ships an update every 6 months, and simos.app every 4 days. Most recently, OBDSTAR was updated on October 9, 2026 and simos.app on October 1, 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.*