# Castor Connect vs Ctrl

The clearest difference is in-app purchases: Castor Connect at none against Ctrl's 2. Castor Connect also leads on device support (3 vs 1) and iOS requirement (13.0 vs 18.0). Ctrl's advantage is update cadence (daily vs every 2 months). On price and ads there is nothing between them.

Both are free to download. Ctrl sells 2 in-app purchases, starting at $6.99 per month. Castor Connect asks for nothing beyond the download.

Castor Connect ships an update every 2 months, Ctrl daily. The most recent releases landed on November 7, 2026 and November 13, 2026 respectively.

## The numbers

| Metric | Castor Connect | Ctrl |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Daily** |
| Monetization | Free | — |
| Size | 28 MB | 62 MB |
| Requires iOS | **13.0** | 18.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [Ciwit B.V.](https://appshunter.io/developer/1009756772) | [You're In Ctrl, Inc.](https://appshunter.io/developer/6797585411) |

## What reviewers say

### Castor Connect

[App page](https://appshunter.io/ios/app/castor-connect/id1532340302)

This app allows study participants to securely complete electronic patient-reported outcome (ePRO) questionnaires on their mobile devices. It offers offline data storage and manual syncing for flexibility. Access requires an invitation or activation code.

**Highlights:** ePRO questionnaire completion, Offline data storage, Manual data sync, Secure participant data, Native mobile application

**In-app purchases:** none


### Ctrl

[App page](https://appshunter.io/ios/app/ctrl-attention-on-purpose/id6797585409)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Ctrl Premium (Monthly) | $6.99 | per month |
| Ctrl Premium (Yearly) | $49.99 | per year |


## Frequently asked questions

### Is Castor Connect free?

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

### Is Ctrl free?

Ctrl is free to download, with in-app purchases available.

### Do Castor Connect or Ctrl have ads?

Neither Castor Connect nor Ctrl shows ads.

### Which is updated more often, Castor Connect or Ctrl?

Castor Connect ships an update every 2 months, and Ctrl daily. Most recently, Castor Connect was updated on November 7, 2026 and Ctrl on November 13, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*