# ErgData vs D

The clearest difference is update cadence: ErgData at fortnightly against D's every 34 months. 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.

ErgData ships an update fortnightly, D every 34 months. The most recent releases landed on October 22, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | ErgData | D |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (5.9K ratings)](https://appshunter.io/ios/app/ergdata/id561716382/reviews)** | — |
| Number of ratings | **5.9K** | — |
| Positive reviews | 45.6% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 34 months |
| Monetization | Free | — |
| Size | 76 MB | 11 MB |
| Requires iOS | 16.0 | **15.6** |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Concept2, Inc.](https://appshunter.io/developer/446481798) | [Sr Technology Co., Ltd.](https://appshunter.io/developer/1225091618) |

## What reviewers say

### ErgData

[App page](https://appshunter.io/ios/app/ergdata/id561716382)

This app acts as a personal training partner for Concept2 equipment. It allows users to set up custom workouts, view real-time stats, track progress, and sync data with online platforms. It also offers workout of the day challenges and detailed post-workout analysis.

**Highlights:** Custom workout setup, Real-time workout stats, Progress tracking, Sync with Concept2 Logbook, Workout of the Day, Post-workout analysis, Apple Watch compatibility

**Features:** Apple Watch app

**In-app purchases:** none

**What reviewers like**

- 🚀 Great app
- 👍 Excellent stats
- 👍 Easy to use
- 👍 Seamless sync with Concept2 logbook
- 👍 Customizable heart rate zones

**What reviewers complain about**

- 🐛 Connection issues with PM5
- 🐛 Unreliable heart rate monitoring
- 🐛 Sync issues with Apple Health
- 🐛 Crashes and data loss
- 🐛 Frequent disconnections

**Reported bugs**

- Workout data not saving
- Heart rate data freezing
- Disconnects during workouts
- Sync issues with Apple Health and Strava
- Login issues and frequent logouts

**Requested features**

- Add friend mode
- Integrate Apple Watch support
- Add manual workout entry
- Implement landscape mode for iPad
- Integrate pace calculator


### D

[App page](https://appshunter.io/ios/app/d-fit/id1606662562)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is ErgData free?

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

### Is D free?

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

### Do ErgData or D have ads?

Neither ErgData nor D shows ads.

### Which is updated more often, ErgData or D?

ErgData ships an update fortnightly, and D every 34 months. Most recently, ErgData was updated on October 22, 2026 and D 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.*