# JJ Solar vs FourStage

The clearest difference is update cadence: JJ Solar at fortnightly against FourStage's every 4 months. On price, ads, in-app purchases and device support there is nothing between them.

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

JJ Solar ships an update fortnightly, FourStage every 4 months. The most recent releases landed on October 24, 2026 and October 27, 2026 respectively.

## The numbers

| Metric | JJ Solar | FourStage |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 4 months |
| Monetization | Free | — |
| Size | 56 MB | 149 MB |
| Requires iOS | 13.4 | **13.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 17+ |
| Developer | [AHASOLAR TECHNOLOGIES LIMITED](https://appshunter.io/developer/1632224285) | [Vertical Axion, LLC](https://appshunter.io/developer/1697138155) |

## What reviewers say

### JJ Solar

[App page](https://appshunter.io/ios/app/jj-solar/id1486782756)

This platform connects consumers with solar energy solutions. It facilitates the estimation of solar PV installations, communication with providers, online payments, and scheduling of site visits for a seamless green energy transition.

**Highlights:** Solar PV installation estimation, Connect with solar providers, Online payment processing, Schedule site visits, Track earnings, Plan daily activities

**In-app purchases:** none


### FourStage

[App page](https://appshunter.io/ios/app/fourstage/id6451203518)

**Features:** macOS Compatibility, Apple Wallet

**In-app purchases:** none


## Frequently asked questions

### Is JJ Solar free?

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

### Is FourStage free?

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

### Do JJ Solar or FourStage have ads?

Neither JJ Solar nor FourStage shows ads.

### Which is updated more often, JJ Solar or FourStage?

JJ Solar ships an update fortnightly, and FourStage every 4 months. Most recently, JJ Solar was updated on October 24, 2026 and FourStage on October 27, 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.*