# Solar Panel Layout vs SunStem

The clearest difference is in-app purchases: SunStem at none against Solar Panel Layout's 2. Solar Panel Layout's advantage is iOS requirement (15.0 vs 17.0). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Solar Panel Layout sells 2 in-app purchases, starting at $2.99 per month. SunStem asks for nothing beyond the download.

Both ship on a similar rhythm, roughly weekly. The most recent releases landed on September 23, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | Solar Panel Layout | SunStem |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Weekly | Weekly |
| Size | 27 MB | 7 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Frederic Billon](https://appshunter.io/developer/1811407676) | [Dmitriy Motorin](https://appshunter.io/developer/1495533596) |

## What reviewers say

### Solar Panel Layout

[App page](https://appshunter.io/ios/app/solar-panel-layout/id6785808578)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro | $2.99 | per month |
| Pro | $17.99 | per year |


### SunStem

[App page](https://appshunter.io/ios/app/sunstem-solar-calculator/id6787007719)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Solar Panel Layout free?

Solar Panel Layout is free to download, with in-app purchases available.

### Is SunStem free?

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

### Do Solar Panel Layout or SunStem have ads?

Neither Solar Panel Layout nor SunStem shows ads.

### Which is updated more often, Solar Panel Layout or SunStem?

Solar Panel Layout ships an update weekly, and SunStem weekly. Most recently, Solar Panel Layout was updated on September 23, 2026 and SunStem on September 18, 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.*