Watta vs ErgData: Smarter Erg Analytics vs the Official Companion App
By the Watta Team · Updated
Quick Verdict
ErgData is Concept2's official free companion app. It connects to the PM5 via Bluetooth to display real-time data, force curves, and interval breakdowns on your phone — and syncs results to the Concept2 Logbook. It does exactly what Concept2 designed it to do: mirror and store PM5 data. Watta goes further by turning that data into insight — a composite Effort Score, heart rate zone analysis, pacing evaluation, and social features. Many rowers use both: ErgData during the workout for force curves, Watta after for the analysis.
Feature Comparison
| Feature | Watta | ErgData |
|---|---|---|
| Data Capture | AI OCR — photograph your PM5 screen post-workout | Bluetooth connection to PM5 for real-time data streaming and storage |
| Force Curve | Not captured (economy is measured via watts per stroke) | Real-time force curve display during rowing — excellent for technique work |
| Effort/Session Rating | 0-100 Effort Score with four weighted components | No effort rating — displays raw data only (split, watts, distance, stroke rate) |
| Heart Rate Analysis | Karvonen zone per session, estimated zone breakdown from interval screens, Cardiac Load in the Effort Score | Heart rate recording and a heart rate zone view per session; no composite training-load score |
| Concept2 Logbook Sync | Read-only Logbook connection — imports your workouts automatically | Automatic sync to Concept2 Online Logbook after every session |
| Social Features | Clubs, squads, social feed, leaderboards | No social features; exports to Strava and Garmin Connect via the Logbook, and to Apple Health and Google Fit |
| Analytics & Trends | Split trends, Effort Score history, pacing analysis, workout comparison | Basic workout history; detailed analytics live in the Concept2 Logbook website |
| Price | Free | Free |
Why Choose Watta
- +Effort Score turns raw PM5 data into a meaningful 0-100 session rating — something ErgData does not attempt
- +Heart rate zone analysis with Karvonen method provides training intensity context beyond raw bpm
- +Social layer with clubs, squads, and leaderboards creates community around erg training
Where ErgData Excels
- +Real-time force curve display is invaluable for technique analysis and coaching
- +Official Concept2 product with seamless Logbook sync — the canonical record of your erg history
- +Proven reliability and direct integration with PM5 hardware
Detailed Breakdown
ErgData is the natural starting point for any Concept2 owner. It is free, official, and it works. The force curve display alone makes it worth having — no other app shows you stroke-by-stroke technique feedback as clearly. Its Logbook sync ensures your lifetime metres are tracked in one canonical place. However, ErgData is fundamentally a data mirror, not an analytics platform. It shows you what happened but does not tell you what it means. It does not rate your session, analyse your pacing, calculate training load, or help you understand whether you are improving. Watta picks up where ErgData leaves off. By photographing your PM5 screen or importing your sessions automatically through its read-only Concept2 Logbook connection, Watta applies the Effort Score algorithm — weighing cardiac load, work output, pacing consistency, and stroke economy — to produce a single meaningful number. Over time, your Effort Score trend tells a story that raw split data cannot. Many serious rowers run ErgData during the session for force curves and Logbook sync, then let the session flow into Watta for the deeper analysis layer.
Frequently Asked Questions
Should I use ErgData or Watta?
Does Watta sync to the Concept2 Logbook?
Can ErgData calculate an Effort Score?
Is the force curve important for rowing?
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Every erg counts.
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