# CytoAtlas vs RBCX Calculation Tool

The clearest difference is rating: RBCX Calculation Tool at 4.8 against CytoAtlas's 4.4. CytoAtlas's advantage is update cadence (monthly vs every 15 months). On price, ratings volume, ads and in-app purchases there is nothing between them.

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

RBCX Calculation Tool holds the better App Store score, 4.8 against 4.4. Both are backed by a comparable volume of ratings — 13 and 6 respectively.

CytoAtlas ships an update monthly, RBCX Calculation Tool every 15 months. Both last shipped on October 24, 2026.

## The numbers

| Metric | CytoAtlas | RBCX Calculation Tool |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.4 (13 ratings)](https://appshunter.io/ios/app/cytoatlas/id908735518/reviews) | **[4.8 (6 ratings)](https://appshunter.io/ios/app/rbcx-calculation-tool/id1457982121/reviews)** |
| Number of ratings | **13** | 6 |
| Positive reviews | 87.5% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Monthly** | Every 15 months |
| Monetization | Free | Free |
| Size | 10 MB | 26 MB |
| Requires iOS | 16.0 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 17+ | 4+ |
| Developer | [PROQMS LLC](https://appshunter.io/developer/908735521) | [Terumo BCT](https://appshunter.io/developer/1023483386) |

## What reviewers say

### CytoAtlas

[App page](https://appshunter.io/ios/app/cytoatlas/id908735518)

This medical reference app offers a comprehensive cytopathology guide with over 800 high-quality images and more than 120 diagnostic entities. It features an intuitive interface for quick access to diagnostic criteria, morphologic characteristics, and relevant studies, serving as a valuable learning aid and quick reference for professionals and students.

**Highlights:** Over 800 high-quality slide images, 120+ diagnostic entities, Key morphologic characteristics, Intuitive interface, Zoom and pan image function, Reference to journal articles

**Features:** macOS Compatibility

**In-app purchases:** none


### RBCX Calculation Tool

[App page](https://appshunter.io/ios/app/rbcx-calculation-tool/id1457982121)

This medical tool assists healthcare professionals in estimating the required replacement fluid volume for red blood cell exchange procedures on the Spectra Optia system. It calculates volumes based on patient and fluid data to achieve target Hct and FCR, and can suggest custom primes.

**Highlights:** Estimate replacement fluid volume, Calculate target Hct and FCR, Determine custom prime recommendation, Uses patient and fluid data, Supports Spectra Optia system

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is CytoAtlas free?

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

### Is RBCX Calculation Tool free?

RBCX Calculation Tool is free to download, with no in-app purchases.

### Which has better reviews, CytoAtlas or RBCX Calculation Tool?

RBCX Calculation Tool is rated higher. CytoAtlas averages 4.4 out of 5 from 13 ratings, while RBCX Calculation Tool averages 4.8 from 6 ratings.

### Do CytoAtlas or RBCX Calculation Tool have ads?

Neither CytoAtlas nor RBCX Calculation Tool shows ads.

### Which is updated more often, CytoAtlas or RBCX Calculation Tool?

CytoAtlas ships an update monthly, and RBCX Calculation Tool every 15 months. Most recently, CytoAtlas was updated on October 24, 2026 and RBCX Calculation Tool on October 24, 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.*