# Principle Mirror vs Digital Diaries

The clearest difference is rating: Digital Diaries at 4.8 against Principle Mirror's 4.2. Digital Diaries also leads on review sentiment (67% vs 45%) and ratings volume (222 vs 14). Principle Mirror's advantage is iOS requirement (11.0 vs 16.0). On price, ads, in-app purchases and monetization model there is nothing between them.

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

Digital Diaries holds the better App Store score, 4.8 against 4.2. That said, the two scores are not equally well evidenced: Digital Diaries has 222 ratings behind it against 14, so its average is the more settled of the two. Written reviews point the same way: 45% of Principle Mirror's written reviews are positive against 67% of Digital Diaries's.

Principle Mirror ships an update every 2 months, Digital Diaries every 5 weeks. Both last shipped on October 29, 2026.

## The numbers

| Metric | Principle Mirror | Digital Diaries |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.2 (14 ratings)](https://appshunter.io/ios/app/principle-mirror/id991911319/reviews) | **[4.8 (222 ratings)](https://appshunter.io/ios/app/digital-diaries/id1248078801/reviews)** |
| Number of ratings | 14 | **222** |
| Positive reviews | 45.2% of reviews | **66.7% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 5 weeks** |
| Monetization | Free | Free |
| Size | 1 MB | 94 MB |
| Requires iOS | **11.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Daniel Hooper](https://appshunter.io/developer/419502228) | [Forsta, Inc.](https://appshunter.io/developer/670071637) |

## What reviewers say

### Principle Mirror

[App page](https://appshunter.io/ios/app/principle-mirror/id991911319)

Design interactive user interfaces with this companion app for a popular Mac design tool. Seamlessly open Principle files or mirror your Mac's design work directly to your device.

**Highlights:** Open Principle files, Mirror Principle for Mac, Interactive UI design, Companion app functionality

**Features:** Vision Pro support

**In-app purchases:** none


### Digital Diaries

[App page](https://appshunter.io/ios/app/digital-diaries/id1248078801)

This platform allows researchers to gain deep insights by immersing themselves in the lives of their respondents. Participants can complete activities, answer questions, and share media conveniently, even on the go. It facilitates exploration of emotions, behaviors, and contexts through interactive diaries and discussions.

**Highlights:** Activity-based market research, Respondent immersion, On-the-go participation, Open and closed-ended questions, Photo and video uploads, Participant discussions

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

**In-app purchases:** none


## Frequently asked questions

### Is Principle Mirror free?

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

### Is Digital Diaries free?

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

### Which has better reviews, Principle Mirror or Digital Diaries?

Digital Diaries is rated higher. Principle Mirror averages 4.2 out of 5 from 14 ratings, while Digital Diaries averages 4.8 from 222 ratings.

### Do Principle Mirror or Digital Diaries have ads?

Neither Principle Mirror nor Digital Diaries shows ads.

### Which is updated more often, Principle Mirror or Digital Diaries?

Principle Mirror ships an update every 2 months, and Digital Diaries every 5 weeks. Most recently, Principle Mirror was updated on October 29, 2026 and Digital Diaries on October 29, 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.*