# Flip Clock 3D vs UnderCoverApp

The clearest difference is in-app purchases: UnderCoverApp at none against Flip Clock 3D's 1. UnderCoverApp also leads on ads (none vs shown). Flip Clock 3D's advantage is update cadence (weekly vs every 6 weeks) and iOS requirement (12.0 vs 15.1). On price and device support there is nothing between them.

Both are free to download. Flip Clock 3D sells 1 one-off in-app purchase. UnderCoverApp asks for nothing beyond the download.

Flip Clock 3D ships an update weekly, UnderCoverApp every 6 weeks. The most recent releases landed on September 24, 2026 and September 8, 2026 respectively.

## The numbers

| Metric | Flip Clock 3D | UnderCoverApp |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (24 ratings)](https://appshunter.io/ios/app/flip-clock-3d-study-time/id6670719398/reviews)** | — |
| Number of ratings | **24** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Weekly** | Every 6 weeks |
| Monetization | Free with in-app purchases | — |
| Size | 206 MB | 73 MB |
| Requires iOS | **12.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [乃君 黄](https://appshunter.io/developer/1337343608) | [ADK Technology LLC](https://appshunter.io/developer/1781005245) |

## What reviewers say

### Flip Clock 3D

[App page](https://appshunter.io/ios/app/flip-clock-3d-study-time/id6670719398)

Enhance your workspace with a realistic 3D mechanical flip clock. This app helps improve focus and productivity during work or study sessions by providing a clear time display. Customize with various fonts and themes, and utilize the alarm feature when the app is active.

**Highlights:** Vivid 3D mechanical components, Adjustable viewing angles, 12/24 hour mode switching, Multiple font and theme options, Foreground alarm functionality

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock all contents | $1.99 | one-time |


### UnderCoverApp

[App page](https://appshunter.io/ios/app/undercoverapp/id6757808080)

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

**In-app purchases:** none


## Frequently asked questions

### Is Flip Clock 3D free?

Flip Clock 3D is free to download, with in-app purchases available.

### Is UnderCoverApp free?

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

### Do Flip Clock 3D or UnderCoverApp have ads?

Flip Clock 3D shows ads; UnderCoverApp does not.

### Which is updated more often, Flip Clock 3D or UnderCoverApp?

Flip Clock 3D ships an update weekly, and UnderCoverApp every 6 weeks. Most recently, Flip Clock 3D was updated on September 24, 2026 and UnderCoverApp on September 8, 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.*