# Idle Server Defender vs Sphere TD

The clearest difference is in-app purchases: Idle Server Defender at none against Sphere TD's 10. Sphere TD's advantage is update cadence (every 2 days vs weekly). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Sphere TD sells 10 one-off in-app purchases. Idle Server Defender asks for nothing beyond the download.

Idle Server Defender ships an update weekly, Sphere TD every 2 days. The most recent releases landed on October 7, 2026 and October 5, 2026 respectively.

## The numbers

| Metric | Idle Server Defender | Sphere TD |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.6 (9 ratings)](https://appshunter.io/ios/app/sphere-td/id6753674090/reviews)** |
| Number of ratings | — | **9** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | Yes | Yes |
| Update frequency | Weekly | **Every 2 days** |
| Monetization | — | Free with in-app purchases |
| Size | 169 MB | 332 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 12+ | 12+ |
| Developer | [Thijs de Rechter](https://appshunter.io/developer/1835418078) | [StandardIssueGames](https://appshunter.io/developer/1844319777) |

## What reviewers say

### Idle Server Defender

[App page](https://appshunter.io/ios/app/idle-server-defender/id6751500850)

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

**In-app purchases:** none


### Sphere TD

[App page](https://appshunter.io/ios/app/sphere-td/id6753674090)

A complex tower defense game where you build and upgrade towers to defend against waves of spheres. Strategize with deep customization, resource management, and research to overcome challenges. Offers extensive replayability with numerous levels and modes.

**Highlights:** Tower and projectile customization, 30 base towers with 28+ stats, 33 mods with millions of combinations, Research and crafting system, Tower inventory and energy management, 50 hand-crafted levels and endless mode, Offline and online play with cloud sync

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Au Field Ration | $4.99 | one-time |
| Defender Starter Pack | $7.99 | one-time |
| Au Supply Cache | $9.99 | one-time |
| Galatium Express Token | $9.99 | one-time |
| Galatium Academy Pack | $14.99 | one-time |
| Shadow Broker Vantage | $19.99 | one-time |
| Au Enterprise Fund | $24.99 | one-time |
| Flux Enrichment Grant | $24.99 | one-time |
| Au Strategic Stockpile | $49.99 | one-time |
| Au Global Reserve | $99.99 | one-time |


## Frequently asked questions

### Is Idle Server Defender free?

Idle Server Defender is free to download, with no in-app purchases.

### Is Sphere TD free?

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

### Do Idle Server Defender or Sphere TD have ads?

Both Idle Server Defender and Sphere TD show ads.

### Which is updated more often, Idle Server Defender or Sphere TD?

Idle Server Defender ships an update weekly, and Sphere TD every 2 days. Most recently, Idle Server Defender was updated on October 7, 2026 and Sphere TD on October 5, 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.*