# ContrastRx vs NIS+RISC Prep

The clearest difference is review sentiment: NIS+RISC Prep at 100% against ContrastRx's 50%. NIS+RISC Prep also leads on rating (5.0 vs 4.4) and update cadence (every 9 days vs every 3 weeks). ContrastRx's advantage is price (Free vs $4.99). On ratings volume, ads, in-app purchases and device support there is nothing between them.

ContrastRx is free to download; NIS+RISC Prep costs $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

NIS+RISC Prep holds the better App Store score, 5.0 against 4.4. Both are backed by a comparable volume of ratings — 9 and 11 respectively. Written reviews point the same way: 50% of ContrastRx's written reviews are positive against 100% of NIS+RISC Prep's.

ContrastRx ships an update every 3 weeks, NIS+RISC Prep every 9 days. The most recent releases landed on October 13, 2026 and October 10, 2026 respectively.

## The numbers

| Metric | ContrastRx | NIS+RISC Prep |
| --- | --- | --- |
| Price | **Free** | $4.99 |
| Rating | [4.4 (9 ratings)](https://appshunter.io/ios/app/contrastrx/id619478666/reviews) | **[5.0 (11 ratings)](https://appshunter.io/ios/app/nis-plus-risc-prep/id6764441298/reviews)** |
| Number of ratings | 9 | **11** |
| Positive reviews | 50.0% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 9 days** |
| Monetization | **Free** | Paid |
| Best chart rank | — | **#198** |
| Size | 9 MB | 33 MB |
| Requires iOS | 16.6 | **15.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 17+ | 17+ |
| Developer | [Mayo Clinic](https://appshunter.io/developer/350350016) | [Shawn Thomas](https://appshunter.io/developer/1895782155) |

## What reviewers say

### ContrastRx

[App page](https://appshunter.io/ios/app/contrastrx/id619478666)

Provides quick access to treatment regimens for life-threatening reactions to radiographic contrast agents. Includes clinical descriptions, visual examples, and treatment protocols, along with helpful calculators and information on nephrogenic systemic fibrosis.

**Highlights:** Treatment regimens for contrast reactions, Clinical descriptions and pictorial examples, eGFR calculator, Pediatric dose calculator, Steroid pretreatment regimens, Nephrogenic systemic fibrosis overview

**Features:** Vision Pro support

**In-app purchases:** none


### NIS+RISC Prep

[App page](https://appshunter.io/ios/app/nis-plus-risc-prep/id6764441298)

**Currently charting:** #198 Top Paid · Medical (US App Store)

Prepare for the ABR Core Exam's Non-Interpretive Skills and Radioisotope Safety sections with over 700 board-style questions. Features detailed explanations, progress tracking, and a distraction-free interface with light and dark modes. Syncs progress across iPhone and iPad.

**Highlights:** 700+ board-style questions, Detailed explanations, Progress tracking, Timed test mode, Full-text search, Light and dark mode, Cross-device sync

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

**In-app purchases:** none


## Frequently asked questions

### Is ContrastRx free?

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

### Is NIS+RISC Prep free?

NIS+RISC Prep costs $4.99, with no in-app purchases.

### Which has better reviews, ContrastRx or NIS+RISC Prep?

NIS+RISC Prep is rated higher. ContrastRx averages 4.4 out of 5 from 9 ratings, while NIS+RISC Prep averages 5.0 from 11 ratings.

### Do ContrastRx or NIS+RISC Prep have ads?

Neither ContrastRx nor NIS+RISC Prep shows ads.

### Which is updated more often, ContrastRx or NIS+RISC Prep?

ContrastRx ships an update every 3 weeks, and NIS+RISC Prep every 9 days. Most recently, ContrastRx was updated on October 13, 2026 and NIS+RISC Prep on October 10, 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.*