# System Ascension vs Sphere TD

The clearest difference is price: Sphere TD at Free against System Ascension's $4.99. Sphere TD also leads on review sentiment (100% vs 71%). System Ascension's advantage is in-app purchases (none vs 10) and ads (none vs shown). On update cadence, device support and iOS requirement there is nothing between them.

Sphere TD is free to download; System Ascension costs $4.99 up front. Sphere TD sells 10 one-off in-app purchases. System Ascension asks for nothing beyond the download.

System Ascension holds the better App Store score, 4.8 against 4.6. Both are backed by a comparable volume of ratings — 46 and 10 respectively. Written reviews complicate that: 71% of System Ascension's written reviews are positive against 100% of Sphere TD's, so the app with the better star average is not the one people write more warmly about.

System Ascension ships an update every 5 days, Sphere TD every 3 days. The most recent releases landed on October 28, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | System Ascension | Sphere TD |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | **[4.8 (46 ratings)](https://appshunter.io/ios/app/system-ascension-idle-core/id6742353811/reviews)** | [4.6 (10 ratings)](https://appshunter.io/ios/app/sphere-td/id6753674090/reviews) |
| Number of ratings | **46** | 10 |
| Positive reviews | 71.4% of reviews | **100.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 5 days | **Every 3 days** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 297 MB | 316 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 12+ | 12+ |
| Developer | [Studio Rouleau Inc](https://appshunter.io/developer/933957878) | [StandardIssueGames](https://appshunter.io/developer/1844319777) |

## What reviewers say

### System Ascension

[App page](https://appshunter.io/ios/app/system-ascension-idle-core/id6742353811)

An incremental strategy game where you guide a stranded AI to build a planetary engine. Master energy sources, automate resources, and uncover a sci-fi story. The game features beautiful art, full narration, and cross-platform cloud saving.

**Highlights:** Incremental strategy gameplay, Resource automation, Planetary engine engineering, Sci-fi story, Cross-platform cloud saving, Fully narrated

**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 System Ascension free?

System Ascension costs $4.99, with no in-app purchases.

### Is Sphere TD free?

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

### Which has better reviews, System Ascension or Sphere TD?

System Ascension is rated higher. System Ascension averages 4.8 out of 5 from 46 ratings, while Sphere TD averages 4.6 from 10 ratings.

### Do System Ascension or Sphere TD have ads?

Sphere TD shows ads; System Ascension does not.

### Which is updated more often, System Ascension or Sphere TD?

System Ascension ships an update every 5 days, and Sphere TD every 3 days. Most recently, System Ascension was updated on October 28, 2026 and Sphere TD on October 30, 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.*