# SubSum vs iFocuspace

The clearest difference is update cadence: iFocuspace at every 3 days against SubSum'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.

SubSum ships an update every 4 months, iFocuspace every 3 days. The most recent releases landed on October 12, 2026 and October 10, 2026 respectively.

## The numbers

| Metric | SubSum | iFocuspace |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/ifocuspace/id6773947719/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 3 days** |
| Monetization | — | Free |
| Size | 2 MB | 2 MB |
| Requires iOS | 17 | **16.0** |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [桥 汪](https://appshunter.io/developer/1658027527) | [Chuchen Technology (Xiamen) Co., Ltd](https://appshunter.io/developer/6773947721) |

## What reviewers say

### SubSum

[App page](https://appshunter.io/ios/app/subsum/id6754885566)

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

**In-app purchases:** none


### iFocuspace

[App page](https://appshunter.io/ios/app/ifocuspace/id6773947719)

Transform web content into a paper-like reading experience on E-Ink devices. Enjoy focused reading, study, and writing with features like one-tap casting, reverse touch controls, and customizable display options. All operations are performed locally for enhanced privacy.

**Highlights:** Cast web content to E-Ink devices, Add any URL as a web app, Reverse touch controls on E-Ink screen, Customizable font size and tap zones, Local data processing for privacy

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is SubSum free?

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

### Is iFocuspace free?

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

### Do SubSum or iFocuspace have ads?

Neither SubSum nor iFocuspace shows ads.

### Which is updated more often, SubSum or iFocuspace?

SubSum ships an update every 4 months, and iFocuspace every 3 days. Most recently, SubSum was updated on October 12, 2026 and iFocuspace on October 10, 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.*