Comparison

Rainbow Sea vs Flat Machine

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

Head to head
About

Rainbow Sea

Embark on a pixel-art adventure where you nurture relationships with seven gods aboard a treasure ship. Your choices shape a bittersweet story with multiple endings, offering replayability. Discover events and uncover the gods' true natures through dialogue and interaction.

Highlights
  • Isometric pixel-art graphics
  • Chiptune-inspired music
  • Branching narrative with multiple endings
  • Relationship building with seven gods
  • Interactive dialogue system
  • Event discovery based on conditions
Read full description

Rainbow Sea is an adventure game with beautiful character designs, isometric pixel-art, nostalgic chiptune-flavored music, and a sometimes funny, sometimes sad story. You can clear this in a couple of hours, but you can play it again and again as the story changes depending on your choices and actions, and there are many ways to reach a single ending. The player spends a year as Human, chosen to be a god, nurturing relationships with the Seven Lucky Gods aboard the treasure ship. You can move freely around the ship by tapping the screen. By talking to the Seven Lucky Gods, you can get their affection. New events will occur under certain conditions such as winning their affection, weather, and events you have seen so far. There are over hundred different types of events. You can find the conditions of each event by watching advertisements, so it is easy to find. Not all of the Seven Lucky Gods characters will open up to you right away, and as you interact with them, you'll start to see what they're up to. You'll start to see what they're dealing with, and since many of them won't reveal their true colors until you get to know them, you may find yourself going through the game with a somewhat unsettled feeling. In addition, Rainbow Sea allows you to lie, so you can hide your true feelings from the Seven Lucky Gods and change the course of the story. You can enjoy character designs that greatly reflect the personalities of each of the Seven Lucky Gods, music which is like a fusion of Japanese style and chiptune, and a bittersweet scenario. We are also planning to update the character graphics and pixel-art animation in the near future.

About

Flat Machine

Control a limbless robot tasked with defending a settlement in a post-apocalyptic world. Engage in simple, timing-based battles against various threats and make choices that influence the game's multiple endings. Discover the mystery of your own identity.

Highlights
  • Simple, timing-based battles
  • Item combination system
  • Respond to various visitors
  • Multiple endings based on choices
  • Daily events and encounters
Features
Read full description

■ Story In the not-so-distant future, a world on the brink of ruin. Awakening in the wasteland is a single robot—with no limbs and no memories. You become the settlement's "gatekeeper," fending off the strange visitors who arrive day after day. Can you protect the settlement through its final days? And what is the true nature of the Flat Machine...? ■ Features [1] Easy, satisfying defense battles—just tap! Tap with the right timing to repel the enemies closing in. Simple to play, yet endlessly strategic through gear and item combinations. Build your own ultimate defense style. [2] Your "choices" change the future—multiple endings Not everyone at the gate is an enemy. Help a struggling mutant, or coldly turn it away? Your decisions steer the story to its ending in this rich sci-fi adventure. [3] Charming pixel art and a wistful apocalyptic world Lovable yet lonely characters brought to life in beautiful retro pixel art. An original atmosphere, deepened by a carefully crafted soundtrack. ■ Perfect for players who love - Pixel-art (retro) games - Dystopian, sci-fi, and apocalyptic worlds - Story-driven indie games - Quick, pick-up-and-play sessions - Tower defense, idle games, and RPGs - Playing free to the end, at your own pace, with no stamina Step into the "everyday apocalypse" woven by an amnesiac gatekeeper robot and the inhabitants of a dying world.

Screenshots

Rainbow Sea4 screens
Flat Machine4 screens

Verdict

The call

The clearest difference is in-app purchases: Rainbow Sea at none against Flat Machine's 4. Rainbow Sea also leads on iOS requirement (12.0 vs 15.0). Flat Machine's advantage is update cadence (every 5 days vs every 6 weeks) and rating (4.9 vs 4.6). On price, ratings volume, ads and device support there is nothing between them.

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. Flat Machine sells 4 one-off in-app purchases. Rainbow Sea asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Flat Machine holds the better App Store score, 4.9 against 4.6. Both are backed by a comparable volume of ratings — 25 and 68 respectively. Written reviews point the same way: 78% of Rainbow Sea's written reviews are positive against 94% of Flat Machine's.

UpkeepUpdate frequency

Rainbow Sea ships an update every 6 weeks, Flat Machine every 5 days. The most recent releases landed on September 29, 2026 and October 15, 2026 respectively.

Scorecard6 real differences · 4 level
Rainbow Sea versus Flat Machine: the parameters behind the verdict, then further details
ParameterRainbow SeaFlat Machine
PriceFreeFree
Rating4.6 (25 ratings)4.9 (68 ratings) — better
Positive reviews77.8% of reviews93.7% of reviews — better
Number of ratings2568 — better
Update frequencyEvery 6 weeksEvery 5 days — better
AdsYesYes
In-app purchasesNo — betterYes
MonetizationAd-supported — betterFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS12.0 — better15.0
Further details — not scored
Size100 MB118 MB
Age rating12+12+
DeveloperRina Okuyamazxima.LLC

Customer experience

Rainbow Sea

All ratings25 ratings
Positive92.0%
Neutral0.0%
Negative8.0%
Written reviews9 reviews
Positive77.8%
Neutral0.0%
Negative22.2%

Flat Machine

All ratings68 ratings
Positive97.1%
Neutral2.9%
Negative0.0%
Written reviews63 reviews
Positive93.7%
Neutral4.8%
Negative1.6%

Bugs and requests

Rainbow Sea

Not enough reviews yet to summarise bugs or requests.

Flat Machine

Reported bugs

4 issues
  • Ads redirect to app store and prevent item rewards
  • Ad BGM continues playing after ad ends
  • Ad BGM persists even after restarting app
  • Agoda ads prevent continuing the game

Requested features

6 requests
  • Add Chinese translation
  • Add Vietnamese translation
  • Add Spanish translation
  • Option for one-time purchase to remove ads
  • More interactions with certain characters (e.g., training robot)
Show 1 more
  • Consider adding taxi or bakery characters in future works

In-app purchases

None

Rainbow Sea

No in-app purchases

4 purchases

Flat Machine

One-time4
  • AD removal$2.99
  • Donation(S)$3.99
  • Donation(M)$14.99
Show 1 more
  • Donation(L)$34.99

Questions

Is Rainbow Sea free?
Rainbow Sea is free to download, with no in-app purchases.
Is Flat Machine free?
Flat Machine is free to download, with in-app purchases available.
Which has better reviews, Rainbow Sea or Flat Machine?
Flat Machine is rated higher. Rainbow Sea averages 4.6 out of 5 from 25 ratings, while Flat Machine averages 4.9 from 68 ratings.
Do Rainbow Sea or Flat Machine have ads?
Both Rainbow Sea and Flat Machine show ads.
Which is updated more often, Rainbow Sea or Flat Machine?
Rainbow Sea ships an update every 6 weeks, and Flat Machine every 5 days. Most recently, Rainbow Sea was updated on September 29, 2026 and Flat Machine on October 15, 2026.

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