# iBigCalc vs Countdown Days

The clearest difference is in-app purchases: iBigCalc at none against Countdown Days's 3. iBigCalc also leads on update cadence (every 3 weeks vs every 5 weeks). Countdown Days's advantage is ads (none vs shown) and iOS requirement (15.6 vs 17). On price and device support there is nothing between them.

Both are free to download. Countdown Days sells 3 in-app purchases, starting at $1.29 per month. iBigCalc asks for nothing beyond the download.

iBigCalc ships an update every 3 weeks, Countdown Days every 5 weeks. The most recent releases landed on October 16, 2026 and October 9, 2026 respectively.

## The numbers

| Metric | iBigCalc | Countdown Days |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | **Every 3 weeks** | Every 5 weeks |
| Size | 5 MB | 45 MB |
| Requires iOS | 17 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Manh Phi Nguyen](https://appshunter.io/developer/1461707344) | [长宏 侯](https://appshunter.io/developer/1726037103) |

## What reviewers say

### iBigCalc

[App page](https://appshunter.io/ios/app/ibigcalc/id6760924865)

**Features:** macOS Compatibility

**In-app purchases:** none


### Countdown Days

[App page](https://appshunter.io/ios/app/countdown-days-events-and-widgets/id6792184671)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro (Monthly) | $1.29 | per month |
| Pro (Yearly) | $9.99 | per year |
| Pro (Lifetime) | $24.99 | one-time |


## Frequently asked questions

### Is iBigCalc free?

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

### Is Countdown Days free?

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

### Do iBigCalc or Countdown Days have ads?

iBigCalc shows ads; Countdown Days does not.

### Which is updated more often, iBigCalc or Countdown Days?

iBigCalc ships an update every 3 weeks, and Countdown Days every 5 weeks. Most recently, iBigCalc was updated on October 16, 2026 and Countdown Days on October 9, 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.*