# 빅스페이스 vs Sumday

The clearest difference is in-app purchases: 빅스페이스 at none against Sumday's 1. 빅스페이스 also leads on ads (none vs shown) and iOS requirement (12.0 vs 15.0). Sumday's advantage is update cadence (every 11 days vs every 9 months). On price and device support there is nothing between them.

Both are free to download. Sumday sells 1 one-off in-app purchase. 빅스페이스 asks for nothing beyond the download.

빅스페이스 ships an update every 9 months, Sumday every 11 days. The most recent releases landed on October 20, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | 빅스페이스 | Sumday |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 9 months | **Every 11 days** |
| Monetization | — | Free with in-app purchases |
| Size | 38 MB | 34 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Cobosys Inc.](https://appshunter.io/developer/1480524814) | [TON CO., LTD.](https://appshunter.io/developer/6796677381) |

## What reviewers say

### 빅스페이스

[App page](https://appshunter.io/ios/app/id6443716298)

**Features:** macOS Compatibility

**In-app purchases:** none


### Sumday

[App page](https://appshunter.io/ios/app/sumday-mental-math-practice/id6802302480)

Sharpen your number sense with daily mental math exercises. This app offers quick arithmetic practice, practical math tricks, and progress tracking to improve your speed and accuracy in just five minutes a day.

**Highlights:** Daily arithmetic questions, Adaptive difficulty levels, Mental math technique cards, Progress tracking and reports, Streak tracking, Offline functionality

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sumday Premium | $3.99 | one-time |


## Frequently asked questions

### Is 빅스페이스 free?

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

### Is Sumday free?

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

### Do 빅스페이스 or Sumday have ads?

Sumday shows ads; 빅스페이스 does not.

### Which is updated more often, 빅스페이스 or Sumday?

빅스페이스 ships an update every 9 months, and Sumday every 11 days. Most recently, 빅스페이스 was updated on October 20, 2026 and Sumday on October 25, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*