Comparison

Idle Monster TD vs Rocket Invaders

Price, ratings, monetisation and update history for both games, side by side — with what reviewers say about each.

Head to head
About

Idle Monster TD

Defend your monster homeland from invading robots in this unique tower defense game. Strategically deploy a variety of monsters with unique skills and elements to stop the mechanical onslaught. Upgrade your defenses and unlock new creatures as you progress through endless waves of enemies.

Highlights
  • Unlock 44 unique elemental monsters
  • Strategic monster placement and synergy
  • 8 diverse defense maps
  • Bi-weekly PvP tournaments
  • Countless upgrades and research options
  • Offline gold earnings
  • Endless gameplay
Features
Read full description

Over 2 million players! Protect the... monsters? As the commander of the United Monsters Alliance, you’ll defend your homeland from menacing machines in Idle Monster TD. This delightful take on tower defense flips the script, putting you in charge of helpful creepy-crawlies trying to stop robot invaders from pummeling your base. Strategically place allies like Sea Stallion for extra-speedy attacks, or use Firefly for heavier damage. And if things get real dicey, just wipe the map clean with a firestorm spell! Eradicating bots gives you upgrades to bolster power, speed, and other stats - and the more bots you obliterate, the more monsters you’ll unlock. Idle Monster TD’s menagerie is filled with awesome beasts, like cute water sprites and scorching fire devils. Discovering new creatures is part of the fun. Like any loyal pal, Idle Monster TD takes care of itself when you’re away. Come back in a few days to claim gold and power up your defenses. Those robots don’t sleep—but neither do your monsters. Features: - Unlock 44 unique monsters of different elements (Water, Air, Earth, and Fire), all of which have different skill sets that make tower synergy crucial to success. - Strategize by placing up to 10 monsters at a time. Determining the most effective combination of their elemental skills and passive boosts will keep you entertained and speculating for weeks! - Play through 8 different maps, each requiring different strategies to defend most efficiently. - Bi-weekly PvP tournaments give this casual game a competitive edge. - Discover countless upgrades, research, spells, artifacts, relics, technology, and more to level up with a variety of different resources. - Several rewarding mini-games, such as Drone Swarms, Cargo Ships, and Tech Ships. - Non-stop, endless gameplay! - Fantasy RPG-based world and classes. - Complete tons of daily missions and achievements. - Offline gold earnings reward you while the game is closed! - Fun and cute pixel artwork. Idle Monster TD is a perfect blend of the Idle and Tower Defense genres. The game is endless and can mostly play itself without you watching. However, an immense amount of strategy is required to play efficiently and place well against your peers on the leaderboards. Go on an epic never-ending quest, explore a fantastic world, battle robots and monsters, and defeat epic bosses in Idle Monster TD!

About

Rocket Invaders

Read full description

The ultimate test of galactic alien defence awaits! A relentless horde of self-replicating Invaders has entered the Solar System, threatening Earth and beyond. With endless waves of hostile spaceships attacking in (surprisingly predictable!) formation, must be destroyed! Now that their surprise assault has failed, it's time to strike back. Protect Earth, clear the Solar System, and harness the enemy Invaders’ own technology to track down and eliminate the source of the invasion! CLASSIC FEATURES * Classic Arcade Shooter – Battle waves of Invaders in dynamic attack patterns. Now with added Motherships! * Upgrade Weapons – Collect crates to unlock and enhance devastating firepower. * Planet-to-Planet Warfare – Travel across the Solar System, planting self-destruction seeds along the way to halt their advance. * Hundreds of Planets – Discover and collect planets, rockets, and Motherships as you progress. NEW FEATURES! * Harvest Resources – Defeated Invaders drop resources—use them to fight back! * Convert Resources – Using the Planetary defence machines, YOU control the amount of Health, Ammo and Fuel you need to fight the invasion! * Load Escape Rockets – Fill your escape rocket with enough fuel to blast off and obliterate everything in your path! A REAL-TIME TEST OF STAMINA! Rocket Invaders combines classic arcade shooting with a fresh challenge, using modern Real-Time Strategy mechanics, delivering a fast-paced, dynamic experience that will push your skills to the limit. The deeper you progress, the more intense the challenge becomes! Can you collect all the planets, destroy all the Motherships and survive every wave of the Invaders? The Universe depends on it!

Screenshots

Idle Monster TD4 screens
Rocket Invaders4 screens

Verdict

The call

Idle Monster TD and Rocket Invaders are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Idle Monster TD sells 11 one-off in-app purchases and Rocket Invaders sells 8 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Idle Monster TD ships an update weekly, Rocket Invaders every 9 days. The most recent releases landed on October 21, 2026 and October 5, 2026 respectively.

ScorecardNo meaningful differences
Idle Monster TD versus Rocket Invaders: the parameters behind the verdict, then further details
ParameterIdle Monster TDRocket Invaders
PriceFreeFree
Rating4.7 (2.6K ratings) — better—
Positive reviews63.0% of reviews—
Number of ratings2.6K — better—
Update frequencyWeekly — betterEvery 9 days
AdsYesYes
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS12.0 — better13.0
Further details — not scored
Size116 MB258 MB
Age rating9+4+
DeveloperSwell Games LLCKrada Studio Corp

Bugs and requests

Idle Monster TD

Reported bugs

5 issues
  • Leaderboards not loading
  • Prestige feature not working as expected
  • Targeting issues with towers
  • Inconsistent ad rewards
  • Essence and currency display issues

Requested features

5 requests
  • Add more monsters and towers
  • Implement offline progression
  • Improve speed options and controls
  • Add more communication features (clans, chat, etc.)
  • Optimize for larger screens (iPad, iPhone X/11)

Rocket Invaders

Not enough reviews yet to summarise bugs or requests.

In-app purchases

11 purchases

Idle Monster TD

One-time11
  • Offline Gold Perk$4.99
  • Tournament Boost$4.99
  • Gems Pack 1$4.99
Show 8 more
  • Ads Bundle$7.99
  • Starter Pack$7.99
  • Game Speed x2$9.99
  • Gems Pack 2$9.99
  • Slayer Bundle$17.99
  • Gems Pack 3$19.99
  • Pro Pack$19.99
  • Resource Pack 5$19.99
8 purchases

Rocket Invaders

One-time8
  • Permanently Unlock All Weapons$0.99
  • Save Sector Progress$0.99
  • Faster Fuel Pipe Transfers$0.99
Show 5 more
  • Slower Bonus Crate Expiry Time$0.99
  • Slower Wave Timers$0.99
  • Remove Ads & Extra Resource$2.99
  • Full Converters at New Planet$2.99
  • Rocket Mega Pack$4.99

Questions

Is Idle Monster TD free?
Idle Monster TD is free to download, with in-app purchases available.
Is Rocket Invaders free?
Rocket Invaders is free to download, with in-app purchases available.
Do Idle Monster TD or Rocket Invaders have ads?
Both Idle Monster TD and Rocket Invaders show ads.
Which is updated more often, Idle Monster TD or Rocket Invaders?
Idle Monster TD ships an update weekly, and Rocket Invaders every 9 days. Most recently, Idle Monster TD was updated on October 21, 2026 and Rocket Invaders on October 5, 2026.

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