# BCTO vs QUARCS

The clearest difference is update cadence: QUARCS at every 6 months against BCTO's every 28 months. BCTO's advantage is iOS requirement (9.0 vs 14.0). 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.

BCTO ships an update every 28 months, QUARCS every 6 months. The most recent releases landed on September 27, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | BCTO | QUARCS |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.0 (1 ratings)](https://appshunter.io/ios/app/quarcs/id6479396546/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 28 months | **Every 6 months** |
| Monetization | — | Free |
| Size | 32 MB | 30 MB |
| Requires iOS | **9.0** | 14.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [佛山市顺德区博通光电有限公司](https://appshunter.io/developer/1269458930) | [Light Speed Vision(Beijing) Co., Ltd](https://appshunter.io/developer/1511662353) |

## What reviewers say

### BCTO

[App page](https://appshunter.io/ios/app/bcto/id1269458931)

**Features:** macOS Compatibility

**In-app purchases:** none


### QUARCS

[App page](https://appshunter.io/ios/app/quarcs/id6479396546)

This open-source software kit enables remote astrophotography capture via Wi-Fi and computer. It offers comprehensive control over telescope mounts, cameras, autoguiding, and electric focusers, integrating with Stellarium for sky mapping.

**Highlights:** Remote capture via Wi-Fi, Computer remote capture via LAN, Mount control, Camera control, Autoguiding, Electric focuser control, Stellarium skymap integration

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is BCTO free?

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

### Is QUARCS free?

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

### Do BCTO or QUARCS have ads?

Neither BCTO nor QUARCS shows ads.

### Which is updated more often, BCTO or QUARCS?

BCTO ships an update every 28 months, and QUARCS every 6 months. Most recently, BCTO was updated on September 27, 2026 and QUARCS on October 6, 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.*