Gt vs simos.app
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Gt
This application enables users to log and configure modern engine and gearbox management systems. It utilizes the UDS protocol over OBD II with open-source OBD BLE devices. The app supports programming recovery if configuration procedures are interrupted.
- Log engine and gearbox management systems
- Configure engine and gearbox management systems
- Supports UDS protocol over OBD II
- Utilizes open-source OBD BLE devices
- Programming recovery for interrupted procedures
- Restart failed configuration attempts
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Application that allows users log and configure modern Engine and Gearbox management systems using the UDS protocol over OBD II using various open source OBD BLE devices. Our application supports programming recovery on most supported platforms if the configuration procedure is interrupted. You can restart the procedure if the previous attempt has failed.
simos.app
This tool provides diagnostic, data logging, and flashing capabilities for specific VAG petrol engine ECUs. It allows real-time monitoring of engine parameters, ECU identification, and analysis of recorded sessions through multi-channel graphs. Users can also update their ECU with stock or custom tunes.
- Real-time ECU parameter logging
- ECU identification
- Multi-channel graph analysis
- ECU and TCU flashing
- Bluetooth LE connection
- Support for Simos 18.x and 12.1 ECUs
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simos.app is a diagnostic, data logging and flashing tool built specifically for VAG petrol engines running Simos 18.1, 18.2, 18.6, 18.10 and Simos 12.1 ECUs. The platforms found in most modern TSI and TFSI engines across Audi, VW, Škoda, SEAT, Cupra and Porsche. LIVE DATA LOGGING Read ECU parameters directly in real time. Monitor boost pressure, injection timing, lambda, temperatures, torque and more at high sample rates over a Bluetooth LE connection. ECU IDENTIFICATION Read software versions, calibration IDs and hardware info straight from the control unit. LOG ANALYSIS Visualize recorded sessions with multi-channel graphs. Spot correlations between parameters without leaving the app. FLASHING Update your ECU and TCU to the latest version for your vehicle or flash a custom tune. Full features available for Simos 18.1/18.10 and 18.6. Flashing stock files or pre-unlocked ecus for Simos 18.2, 18.4, 18.41 and Simos 12.1. –– Built for enthusiasts, tuners and workshops who need more than a generic scan tool. Basic knowledge of ECU diagnostics is recommended. This app is for informational and diagnostic purposes only. Any modifications to vehicle systems are the sole responsibility of the user and must comply with local laws and regulations. –– Bluetooth LE OBD adapter required. Get yours here: https://simos.app/dongle Other compatible adapters: Macchina A0, DIY A0 clone https://github.com/Switchleg1/AMAleg require custom firmware: https://simos.app/dongle/firmware
Screenshots
Verdict
The clearest difference is in-app purchases: Gt at none against simos.app's 3. On price, update cadence, ads and monetization model there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. simos.app sells 3 one-off in-app purchases. Gt asks for nothing beyond the download.
Gt ships an update every 2 weeks, simos.app weekly. The most recent releases landed on October 30, 2026 and October 31, 2026 respectively.
| Parameter | Gt | simos.app |
|---|---|---|
| Price | Free | Free |
| Rating | — | 5.0 (2 ratings) — better |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | — | 2 — better |
| Update frequency | Every 2 weeks | Weekly — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free | Free |
| Devices | iPhone, iPad — better | iPhone |
| Requires iOS | 17.4 — better | 17.6 |
| Further details — not scored | ||
| Size | 55 MB | 6 MB |
| Age rating | 4+ | 4+ |
| Developer | Athanasios Farmakis | Tycho Sebastian Holzer |
Customer experience
Gt
simos.app
In-app purchases
Gt
No in-app purchases
simos.app
- App VIN Unlock$17.99
- Wizard: Pops & Bangs - Single Bin$17.99
- Stage 1 Bin$179.99








