Comparison

Atom Shell vs O

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

Head to head
About

Atom Shell

A puzzle game where players strategically place electrons into inner shells to score points. With over 1000 levels, it offers a challenging and engaging experience for players of all ages.

Highlights
  • Electron placement mechanics
  • Scoring system
  • 1000+ levels
  • Intuitive gameplay
Features
Read full description

* All you have to do is to carefully move the electrons into the inner shells. * Try to place electrons closer to get more score. * 1000+ Levels

About

O

Build an offensive line roster of colored balls that collide and split in real-time. Strategically upgrade your team between plays to advance down the field and score touchdowns in this physics-driven football arcade game.

Highlights
  • Physics-driven ball simulation
  • Roster building and upgrades
  • Unique sticker abilities
  • Two distinct game modes
  • Adaptive adaptive music
  • Real-time collisions and splitting balls
Features
Read full description

O-Line Particle Accelerator is a physics-driven, arcade-style roguelike where you build an offensive line of bouncing, colliding linemen and drive down the field for a touchdown. BUILD YOUR TEAM Build a team of lineman, and drive down the field. Score a touchdown and you win the game! Turn it over and you lose. After each down, use Fantasy Points to upgrade your team, applying unique Boosts and Stickers to give your roster powerful abilities on the field. GREAT OFFLINE PLAY EXPERIENCE This game is free, totally offline, has no ads and collects no data. Perfect game to play on a quick commute on the train, and perfect to sink your teeth into for a multi-hour flight. Also great to play at home if that's your thing! MUSIC, SOUND AND HAPTICS Trancelike adaptive music which changes depending on the phase of the game! ADAPTIVE SOUND: If you'd prefer to listen to your own tunes (or watch Funny Moment Video Compilations while you play), this game dynamically disables and re-enables its music and SFX when background audio/video is playing. SATISFYING HAPTIC FEEDBACK: No sound? No problem! Enjoy the satisfying haptic feedback when your players collide on the field and when the yards are tallied up after each down. CONTENT Plenty of content! 5 UNIQUE STARTING TEAMS: Each team has totally unique strategies and weaknesses. Run with standard rosters, Play as a Whale Family, or manage an Alien Monster that absorbs a teammate every round! 9 DIFFICULTY LEVELS: Each stake dramatically changes the difficulty of the game. Enemy stickers, random injuries, starting from the 0 yard line, and more. ENDLESS MODE: After a touchdown, continue the game with your team as enemies continue to grow stronger exponentially! How many Touchdowns can you score?

Screenshots

Atom Shell4 screens
O4 screens

Verdict

The call

The clearest difference is rating: O at 5.0 against Atom Shell's 4.5. O also leads on update cadence (every 6 weeks vs every 6 months). Atom Shell's advantage is iOS requirement (9.0 vs 26.0). On price, review sentiment, ratings volume and ads 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. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

O holds the better App Store score, 5.0 against 4.5. Both are backed by a comparable volume of ratings — 2 and 4 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

Atom Shell ships an update every 6 months, O every 6 weeks. The most recent releases landed on September 12, 2026 and September 7, 2026 respectively.

Scorecard3 real differences · 7 level
Atom Shell versus O: the parameters behind the verdict, then further details
ParameterAtom ShellO
PriceFreeFree
Rating4.5 (2 ratings)5.0 (4 ratings) — better
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings24 — better
Update frequencyEvery 6 monthsEvery 6 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS9.0 — better26.0
Further details — not scored
Size149 MB68 MB
Age rating4+12+
DeveloperKamran GasimovMATTHEW SCOTT GRANGE

Customer experience

Atom Shell

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

O

Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Atom Shell

No in-app purchases

None

O

No in-app purchases

Questions

Is Atom Shell free?
Atom Shell is free to download, with no in-app purchases.
Is O free?
O is free to download, with no in-app purchases.
Which has better reviews, Atom Shell or O?
O is rated higher. Atom Shell averages 4.5 out of 5 from 2 ratings, while O averages 5.0 from 4 ratings.
Do Atom Shell or O have ads?
Neither Atom Shell nor O shows ads.
Which is updated more often, Atom Shell or O?
Atom Shell ships an update every 6 months, and O every 6 weeks. Most recently, Atom Shell was updated on September 12, 2026 and O on September 7, 2026.

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