# HEIR vs Sunlight Hours

The clearest difference is in-app purchases: HEIR at none against Sunlight Hours's 2. HEIR also leads on ads (none vs shown) and iOS requirement (6.0 vs 16.6). Sunlight Hours's advantage is update cadence (every 3 days vs every 6 months). On price and device support there is nothing between them.

Both are free to download. Sunlight Hours sells 2 one-off in-app purchases. HEIR asks for nothing beyond the download.

HEIR ships an update every 6 months, Sunlight Hours every 3 days. The most recent releases landed on November 1, 2026 and November 4, 2026 respectively.

## The numbers

| Metric | HEIR | Sunlight Hours |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.0 (1 ratings)](https://appshunter.io/ios/app/heir-historic-environment-image-resource/id989286250/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 33.3% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 6 months | **Every 3 days** |
| Monetization | Free | — |
| Size | 30 MB | 44 MB |
| Requires iOS | **6.0** | 16.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 17+ |
| Developer | [Keepthinking Limited](https://appshunter.io/developer/989286249) | [NovaNext](https://appshunter.io/developer/1285557502) |

## What reviewers say

### HEIR

[App page](https://appshunter.io/ios/app/heir-historic-environment-image-resource/id989286250)

Explore thousands of historic photographs and compare them to present-day views. Help researchers track environmental and climate change by re-photographing historical sites and contributing to a global database.

**Highlights:** Access thousands of historic images, Overlay feature for re-photography, Track environmental and heritage change, Contribute to a global database, Explore past and present landscapes

**Features:** macOS Compatibility

**In-app purchases:** none


### Sunlight Hours

[App page](https://appshunter.io/ios/app/sunlight-hours/id6499107039)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Coffee | $0.99 | one-time |
| Remove Ads | $0.99 | one-time |


## Frequently asked questions

### Is HEIR free?

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

### Is Sunlight Hours free?

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

### Do HEIR or Sunlight Hours have ads?

Sunlight Hours shows ads; HEIR does not.

### Which is updated more often, HEIR or Sunlight Hours?

HEIR ships an update every 6 months, and Sunlight Hours every 3 days. Most recently, HEIR was updated on November 1, 2026 and Sunlight Hours on November 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.*