EP Calipers vs The narnar app
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
EP Calipers
This medical app allows users to measure intervals and angles on electrocardiogram (ECG) images. It's designed for healthcare professionals to accurately analyze ECGs from photos or PDFs, aiding in calculations like heart rate and QT intervals.
- Measure ECG intervals
- Measure ECG angles
- Calculate mean heart rate
- Determine corrected QT interval
- Analyze ECG photos and PDFs
- Supports Brugada syndrome beta angle measurement
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EP Calipers provides electronic calipers to measure intervals on images of electrocardiograms (ECGs) or electrophysiologic recordings. Doctors, nurses and medical technicians photograph and send ECGs to each other via email and messaging using smart phones and tablets. It is difficult and inaccurate to make measurements on these images with mechanical calipers. EP Calipers can be used to make accurate ECG measurements and do calculations such as determining mean heart rate and corrected QT interval. Angles such as the beta angle in Brugada syndrome can be measured as well. Analyze ECG images you photograph or store on your device, as well as PDF files, such as ECGs generated by the AliveCor Kardia™ device.
The narnar app
This application aids researchers in processing and quantifying perfusion studies for contrast-enhanced ultrasound. It supports various organs and research protocols, offering real-time analysis of microvascular blood flow.
- Perfusion study processing
- Quantification of microvascular blood flow
- Supports various organs and research protocols
- Automatic and manual image alignment
- Real-time time-videointensity curve analysis
- Parametric imaging of blood flow
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The narnar app for contrast-enhanced ultrasound (CEUS) allows researchers to process and quantify perfusion studies of various organs (e.g., heart, kidney, liver, skeletal muscle), acquired across a range of research protocols, including cardiac realtime, cardiac triggered and generic realtime studies. Key features include: • Automatic and manual image alignment • Color-coding of digitally-subtracted images • Averaged and maximum intensity projection (MIP) imaging • Quantification and modeling of microvascular blood flow from time-videointensity curves, calculated in real-time. • Parametric imaging of blood flow and velocity
Screenshots
Verdict
The clearest difference is review sentiment: EP Calipers at 50% against The narnar app's 0%. EP Calipers also leads on chart position (#106 vs unranked). The narnar app's advantage is price (Free vs $1.99) and rating (4.8 vs 2.3). On ratings volume, update cadence, ads and in-app purchases 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
The narnar app is free to download; EP Calipers costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.
The narnar app holds the better App Store score, 4.8 against 2.3. Both are backed by a comparable volume of ratings — 6 and 8 respectively. Written reviews complicate that: 50% of EP Calipers's written reviews are positive against 0% of The narnar app's, so the app with the better star average is not the one people write more warmly about.
Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on November 11, 2026 and November 2, 2026 respectively.
| Parameter | EP Calipers | The narnar app |
|---|---|---|
| Price | $1.99 | Free — better |
| Rating | 2.3 (6 ratings) | 4.8 (8 ratings) — better |
| Positive reviews | 50.0% of reviews — better | 0.0% of reviews |
| Number of ratings | 6 | 8 — better |
| Update frequency | Every 3 months | Every 3 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Free — better |
| Best chart rank | #106 — better | — |
| Devices | iPhone, iPad — better | iPad |
| Requires iOS | 17.6 | 14.3 — better |
| Further details — not scored | ||
| Size | 14 MB | 13 MB |
| Age rating | 12+ | 12+ |
| Developer | EP Studios | narnar, LLC |
Customer experience
EP Calipers
The narnar app
In-app purchases
EP Calipers
No in-app purchases
The narnar app
No in-app purchases
Questions
Is EP Calipers free?
Is The narnar app free?
Which has better reviews, EP Calipers or The narnar app?
Do EP Calipers or The narnar app have ads?
Which is updated more often, EP Calipers or The narnar app?
Other comparisons
