# Sync vs Merge Defense 3D!

The clearest difference is review sentiment: Sync at 97% against Merge Defense 3D!'s 25%. Sync also leads on rating (4.8 vs 3.7) and in-app purchases (none vs 5). Merge Defense 3D!'s advantage is price (Free vs $0.99) and update cadence (every 3 weeks vs every 40 months). On device support and iOS requirement there is nothing between them.

Merge Defense 3D! is free to download; Sync costs $0.99 up front. Merge Defense 3D! sells 5 one-off in-app purchases. Sync asks for nothing beyond the download.

Sync holds the better App Store score, 4.8 against 3.7. That said, the two scores are not equally well evidenced: Merge Defense 3D! has 1.1K ratings behind it against 33, so its average is the more settled of the two. Written reviews point the same way: 97% of Sync's written reviews are positive against 25% of Merge Defense 3D!'s.

Sync ships an update every 40 months, Merge Defense 3D! every 3 weeks. The most recent releases landed on September 10, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | Sync | Merge Defense 3D! |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | **[4.8 (33 ratings)](https://appshunter.io/ios/app/sync-ball/id356277312/reviews)** | [3.7 (1.1K ratings)](https://appshunter.io/ios/app/merge-defense-3d/id1490412270/reviews) |
| Number of ratings | 33 | **1.1K** |
| Positive reviews | **96.8% of reviews** | 24.5% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 40 months | **Every 3 weeks** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 9 MB | 157 MB |
| Requires iOS | **12.0** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Tozai, Inc.](https://appshunter.io/developer/356277315) | [Tatem Games Inc.](https://appshunter.io/developer/1259148330) |

## What reviewers say

### Sync

[App page](https://appshunter.io/ios/app/sync-ball/id356277312)

Engage your mind with a unique puzzle experience where you guide synchronized balls to designated holes using simple swipes. Navigate through increasingly complex mazes, strategically using walls to achieve your goals. Enjoy a tranquil yet stimulating challenge with 80 levels, designed for thoughtful problem-solving without time pressure.

**Highlights:** Swipe to move synchronized balls, Align balls into holes, Use maze walls for strategy, Avoid falling off the platform, Progress through 80 levels, No time limits or scores, Develop concentration and problem-solving skills

**Features:** macOS Compatibility

**In-app purchases:** none


### Merge Defense 3D!

[App page](https://appshunter.io/ios/app/merge-defense-3d/id1490412270)

A turn-based tower defense game where players strategically place and merge defenders to fend off advancing enemy blocks. It offers offline play and a challenging puzzle experience for a daring mind.

**Highlights:** Turn-based gameplay, Merge defenders to upgrade, Strategic placement, Offline play, Challenging puzzle, Power-ups and unlocks

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pack of Gems | $0.99 | one-time |
| Double Gems | $1.99 | one-time |
| Remove Ads | $2.99 | one-time |
| Promo Bundle | $3.99 | one-time |
| Big Promo Bundle | $6.99 | one-time |

**What reviewers like**

- ⭐ Good game concept
- 🎮 Enjoyable gameplay
- 💎 Addictive

**What reviewers complain about**

- 💸 Excessive ads
- 🔁 Ads interrupt gameplay
- 🔒 Paid ad-free version doesn't work
- 🐛 Glitches and crashes
- 🔋 Drains battery quickly

**Reported bugs**

- Paid ad-free version doesn't remove ads
- Game freezes during ads
- Progress lost when game crashes

**Requested features**

- Add 'End Turn' button
- Improve difficulty scaling past level 1000
- Increase max level for defense towers


## Frequently asked questions

### Is Sync free?

Sync costs $0.99, with no in-app purchases.

### Is Merge Defense 3D! free?

Merge Defense 3D! is free to download, with in-app purchases available.

### Which has better reviews, Sync or Merge Defense 3D!?

Sync is rated higher. Sync averages 4.8 out of 5 from 33 ratings, while Merge Defense 3D! averages 3.7 from 1.1K ratings.

### Do Sync or Merge Defense 3D! have ads?

Merge Defense 3D! shows ads; Sync does not.

### Which is updated more often, Sync or Merge Defense 3D!?

Sync ships an update every 40 months, and Merge Defense 3D! every 3 weeks. Most recently, Sync was updated on September 10, 2026 and Merge Defense 3D! on September 24, 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.*