# Penned vs Erebus Solar

The clearest difference is review sentiment: Penned at 50% against Erebus Solar's 0%. Penned also leads on rating (4.6 vs 3.7) and ratings volume (87 vs 3). Erebus Solar's advantage is price (Free vs $4.99) and update cadence (every 2 weeks vs every 2 months). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

Erebus Solar is free to download; Penned costs $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Penned holds the better App Store score, 4.6 against 3.7. That said, the two scores are not equally well evidenced: Penned has 87 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 50% of Penned's written reviews are positive against 0% of Erebus Solar's.

Penned ships an update every 2 months, Erebus Solar every 2 weeks. The most recent releases landed on October 10, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | Penned | Erebus Solar |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | **[4.6 (87 ratings)](https://appshunter.io/ios/app/penned-private-notes/id1480653765/reviews)** | [3.7 (3 ratings)](https://appshunter.io/ios/app/erebus-solar/id6790828521/reviews) |
| Number of ratings | **87** | 3 |
| Positive reviews | **50.0% of reviews** | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 2 weeks** |
| Monetization | Paid | **Free** |
| Size | 1 MB | 19 MB |
| Requires iOS | **16.6** | 17.0 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Edwing H Santos Mena](https://appshunter.io/developer/1851857999) | [Todd Evans](https://appshunter.io/developer/6790828523) |

## What reviewers say

### Penned

[App page](https://appshunter.io/ios/app/penned-private-notes/id1480653765)

A minimalist handwriting app designed for privacy, keeping all your notes securely on your device. It features natural writing with Apple Pencil, on-device AI text recognition, and smart tagging for easy searching. Export your notes as PDFs in a clean, distraction-free interface.

**Highlights:** Natural Apple Pencil writing, On-device AI text recognition, 100% private, no cloud, Export beautiful PDFs, Smart tagging and search, Distraction-free interface

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

**In-app purchases:** none


### Erebus Solar

[App page](https://appshunter.io/ios/app/erebus-solar/id6790828521)

This app helps solar professionals measure on-site shade using their phone's sensors. It generates horizon files compatible with leading PV design software, aiding in accurate solar production estimates.

**Highlights:** AR sun path visualization, Automatic sky capture, Sky Editor for obstruction tracing, Annual solar access analysis, PDF shade report export, Horizon file generation for design tools, Project organization by site

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

**In-app purchases:** none


## Frequently asked questions

### Is Penned free?

Penned costs $4.99, with no in-app purchases.

### Is Erebus Solar free?

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

### Which has better reviews, Penned or Erebus Solar?

Penned is rated higher. Penned averages 4.6 out of 5 from 87 ratings, while Erebus Solar averages 3.7 from 3 ratings.

### Do Penned or Erebus Solar have ads?

Neither Penned nor Erebus Solar shows ads.

### Which is updated more often, Penned or Erebus Solar?

Penned ships an update every 2 months, and Erebus Solar every 2 weeks. Most recently, Penned was updated on October 10, 2026 and Erebus Solar on October 14, 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.*