# Underdark vs 啟TD

The clearest difference is device support: Underdark at 3 against 啟TD's 1. Underdark also leads on iOS requirement (13.0 vs 16.0). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Underdark sells 34 one-off in-app purchases and 啟TD sells 5 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

Underdark ships an update every 4 days, 啟TD every 6 days. The most recent releases landed on October 20, 2026 and October 10, 2026 respectively.

## The numbers

| Metric | Underdark | 啟TD |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (4.1K ratings)](https://appshunter.io/ios/app/underdarkdefense/id6482025287/reviews)** | — |
| Number of ratings | **4.1K** | — |
| Positive reviews | 72.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | **Every 4 days** | Every 6 days |
| Monetization | Free with in-app purchases | — |
| Size | 508 MB | 1.1 GB |
| Requires iOS | **13.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 12+ |
| Developer | [SeungHo Chung](https://appshunter.io/developer/1626940418) | [Chin-Hsuan Chang](https://appshunter.io/developer/6789075953) |

## What reviewers say

### Underdark

[App page](https://appshunter.io/ios/app/underdarkdefense/id6482025287)

Defend the Eternal Flame from relentless dark forces in this tactical tower defense game. Strategically place towers, choose buffs, and level up your heroes to forge an impenetrable defense. Enjoy one-handed gameplay for strategic fun anytime, anywhere.

**Highlights:** Defend the Eternal Flame, One-handed gameplay, Customize defense strategy, Level up and choose buffs, Hero abilities and enhancements, Earn trophies

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

**In-app purchases (34)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Event Package 1 | $0.99 | one-time |
| daily_package_01 | $0.99 | one-time |
| season_growth_1 | $0.99 | one-time |
| dailyshop_1 | $1.99 | one-time |
| blade_pakcage | $2.99 | one-time |
| daily_package_02 | $2.99 | one-time |
| exp_2x | $3.49 | one-time |
| skin_30501 | $3.49 | one-time |
| Event Package 2 | $3.99 | one-time |
| pet_package | $4.99 | one-time |
| weekly_package_01 | $6.99 | one-time |
| add_speed | $7.49 | one-time |
| pass_hero_115 | $7.49 | one-time |
| pass_hero_102 | $7.49 | one-time |
| pass_hero_110 | $7.49 | one-time |
| season_superpass_1 | $7.99 | one-time |
| pack_remove_ads | $7.99 | one-time |
| daily_package_03 | $7.99 | one-time |
| hero_legend_santa | $8.99 | one-time |
| hero_legend_tower | $8.99 | one-time |
| hero_legend_armor | $8.99 | one-time |
| Event Package 3 | $8.99 | one-time |
| hero_legend_joker | $8.99 | one-time |
| hero_legend_necromancer | $8.99 | one-time |
| hero_legend_chicken | $8.99 | one-time |
| tower_legend_614 | $8.99 | one-time |
| ud_pack_20106 | $8.99 | one-time |
| tower_legend_628 | $8.99 | one-time |
| pack_remove_ads2 | $10.99 | one-time |
| Event Package 4 | $12.99 | one-time |
| season_level_1 | $16.99 | one-time |
| season_stage_1 | $16.99 | one-time |
| Event Package 5 | $17.99 | one-time |
| season_hyperpass_1 | $18.99 | one-time |

**What reviewers like**

- 🚀 Addictive gameplay
- 👍 Generous with rewards
- 🚀 Smooth performance
- 👍 No forced ads
- 👍 Unique tower defense mechanics

**What reviewers complain about**

- 🐛 Multiplayer issues
- 🔋 Battery drain
- 🔒 Paywall for progression
- 🔒 Excessive microtransactions
- 🔒 Confusing UI with too many menus

**Reported bugs**

- Goblin tower factory causing game slowdown
- Consecutive login rewards reset after updates
- Invisible towers in multiplayer

**Requested features**

- Ability to rotate towers
- Move towers after placement
- More enemy variety and animations
- Improved co-op mode
- Simplified progression system


### 啟TD

[App page](https://appshunter.io/ios/app/td/id6799102248)

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

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 300 鑽石 | $0.99 | one-time |
| 800 鑽石 | $1.99 | one-time |
| 2,000 鑽石 | $3.99 | one-time |
| 5,000 鑽石 | $9.99 | one-time |
| 60,000 鑽石 | $99.99 | one-time |


## Frequently asked questions

### Is Underdark free?

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

### Is 啟TD free?

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

### Do Underdark or 啟TD have ads?

Both Underdark and 啟TD show ads.

### Which is updated more often, Underdark or 啟TD?

Underdark ships an update every 4 days, and 啟TD every 6 days. Most recently, Underdark was updated on October 20, 2026 and 啟TD on October 10, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*