# Caris+ vs Primum

The clearest difference is ads: Caris+ at none against Primum's shown. Caris+ also leads on rating (4.4 vs 4.2) and monetization model (free vs ad-supported). Primum's advantage is review sentiment (100% vs 67%). On price, ratings volume, update cadence 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.

Caris+ holds the better App Store score, 4.4 against 4.2. Both are backed by a comparable volume of ratings — 7 and 5 respectively. Written reviews complicate that: 67% of Caris+'s written reviews are positive against 100% of Primum's, so the app with the better star average is not the one people write more warmly about.

Caris+ ships an update monthly, Primum every 2 months. The most recent releases landed on September 17, 2026 and August 4, 2026 respectively.

## The numbers

| Metric | Caris+ | Primum |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (7 ratings)](https://appshunter.io/ios/app/caris-plus/id1485422809/reviews)** | [4.2 (5 ratings)](https://appshunter.io/ios/app/primum/id6651755259/reviews) |
| Number of ratings | **7** | 5 |
| Positive reviews | 66.7% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | **Monthly** | Every 2 months |
| Monetization | **Free** | Ad-supported |
| Size | 23 MB | 53 MB |
| Requires iOS | 16.0 | **15.1** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 17+ | 17+ |
| Developer | [Caris MPI, Inc.](https://appshunter.io/developer/1485422808) | [PRIMUM HEALTH, INC.](https://appshunter.io/developer/1707581637) |

## What reviewers say

### Caris+

[App page](https://appshunter.io/ios/app/caris-plus/id1485422809)

Access and manage your Caris profiling cases on the go. View patient results, track testing progress, and receive real-time notifications. Approve orders and explore interactive results with potential clinical trial matches.

**Highlights:** View and search cases, Real-time case notifications, Track testing progress, Approve orders, Interactive results, Clinical trial matching, Request molecular tumor board review

**Features:** macOS Compatibility

**In-app purchases:** none


### Primum

[App page](https://appshunter.io/ios/app/primum/id6651755259)

Connect with expert oncologists for case-specific advice and treatment decision support. This app facilitates direct messaging with specialists, offering actionable insights and a platform to manage your inquiries efficiently.

**Highlights:** Search and filter expert oncologists, Direct messaging with specialists, Real-time chat and notifications, Case-specific advice, Inbox management, Reference past inquiries

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Caris+ free?

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

### Is Primum free?

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

### Which has better reviews, Caris+ or Primum?

Caris+ is rated higher. Caris+ averages 4.4 out of 5 from 7 ratings, while Primum averages 4.2 from 5 ratings.

### Do Caris+ or Primum have ads?

Primum shows ads; Caris+ does not.

### Which is updated more often, Caris+ or Primum?

Caris+ ships an update monthly, and Primum every 2 months. Most recently, Caris+ was updated on September 17, 2026 and Primum on August 4, 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.*