# First vs OTR Diagnostics

The clearest difference is rating: OTR Diagnostics at 4.0 against First's 2.3. OTR Diagnostics also leads on review sentiment (55% vs 17%) and update cadence (fortnightly vs every 5 months). First's advantage is monetization model (free vs free with in-app purchases) and iOS requirement (11.0 vs 17.6). On price, ads, in-app purchases and device support there is nothing between them.

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

OTR Diagnostics holds the better App Store score, 4.0 against 2.3. That said, the two scores are not equally well evidenced: OTR Diagnostics has 99 ratings behind it against 16, so its average is the more settled of the two. Written reviews point the same way: 17% of First's written reviews are positive against 55% of OTR Diagnostics's.

First ships an update every 5 months, OTR Diagnostics fortnightly. The most recent releases landed on October 5, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | First | OTR Diagnostics |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.3 (16 ratings)](https://appshunter.io/ios/app/first-link/id1203747139/reviews) | **[4.0 (99 ratings)](https://appshunter.io/ios/app/otr-diagnostics/id1508165885/reviews)** |
| Number of ratings | 16 | **99** |
| Positive reviews | 16.7% of reviews | **55.2% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 months | **Fortnightly** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 128 MB | 267 MB |
| Requires iOS | **11.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Snap-on Inc.](https://appshunter.io/developer/501219324) | [OTR Performance](https://appshunter.io/developer/1508165884) |

## What reviewers say

### First

[App page](https://appshunter.io/ios/app/first-link/id1203747139)

Connect your mobile device to a commercial vehicle's diagnostic port to monitor its health status. Understand fault codes, view vehicle specifications, and track trip data to improve uptime and aid in service and repair.

**Highlights:** Connect to vehicle diagnostic port, Monitor vehicle health status, View active and inactive fault codes, Display vehicle specifications (VIN, ECU info), Track trip data (fuel, miles, speed, hours), Generate and share vehicle reports

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

**In-app purchases:** none


### OTR Diagnostics

[App page](https://appshunter.io/ios/app/otr-diagnostics/id1508165885)

This app helps heavy-duty truck owners diagnose and resolve common issues like fault codes, regen problems, and derates. It provides plain-language explanations of error codes, allows for bi-directional commands to fix issues, and monitors live truck data to prevent downtime.

**Highlights:** AI-powered fault code explanation, Bi-directional commands for repairs, Reset active/inactive fault codes, Run forced DPF/SCR regens, Live data monitoring, Fault code history tracking

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

**In-app purchases:** none

**What reviewers like**

- 💰 Saves money on repairs
- 🛠️ Clears fault codes
- 🔄 Performs forced regens
- ✅ Works with various engines
- 👍 Easy to use

**What reviewers complain about**

- 💸 Overpriced
- 🐛 Buggy and unstable app
- 🔌 Frequent Bluetooth disconnects
- 📉 Updates cause problems
- ❌ Some features disappeared after updates

**Reported bugs**

- App constantly disconnects from device
- Generic code option disappeared
- Forced regen is no longer consistent
- AI assistant not working
- App asks to do things not available in app

**Requested features**

- Remember email address for login
- Allow offline functionality without data connection
- Add option to change speed
- More detailed diagnostic information
- Allow basic subscription to work on multiple VINs


## Frequently asked questions

### Is First free?

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

### Is OTR Diagnostics free?

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

### Which has better reviews, First or OTR Diagnostics?

OTR Diagnostics is rated higher. First averages 2.3 out of 5 from 16 ratings, while OTR Diagnostics averages 4.0 from 99 ratings.

### Do First or OTR Diagnostics have ads?

Neither First nor OTR Diagnostics shows ads.

### Which is updated more often, First or OTR Diagnostics?

First ships an update every 5 months, and OTR Diagnostics fortnightly. Most recently, First was updated on October 5, 2026 and OTR Diagnostics on October 6, 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.*