- Oppidum Závist
- Opposites - HD
- Opposites 1
- Opposites 2 - Matching game
- Opposites Adventure
- Opposites Fun Deck
- Opposites learn and play
- OPQA
- Opstapp App
- Optima Poker Trainer
- OptelSpel
- Optical illusion hypnosis
- Optical Illusions:Brain Teaser
- Optical Inquisitor 17+
- Optical Inquisitor Zero
- OptiFlight
- Opulent House Escape
- OPUS: Rocket of Whispers
- OPYC
- Oracle - Ask anything
- Oralbums - Boucle d'or
- Oralbums - La Moufle
- Oralbums - Les 3 Petits Cochons
- Oran's Table
- Orange
- Orange Alert
- Orange Bouncing Ball
- Orange Crash
- Orange Genius
- Orange HD
- Orange Juice Brick Breaker
- Orange Pen
- Orange Season
- Orange to Juice Puzzle
- Orange Tree
- Orange.
- Orangerie de Pol - the game
- Orb Clans
- Orb Defense AR
- Orb Heroes
- Orb Defense AR
- Orb Heroes
- Orb Lines, Neo Lines 98
- Orb Master
- Orb Wars
- Orb.
- Orba
- Orbeez – O resgate dos Woozers
- Orbi.go - reach the center
- Orbia
- Orbit - Defy gravity
- ORBIT - multiplayer space battles!
- Orbit 2D
- ORBIT AR
- Orbit Arcadia
- Orbit Bender
- Orbit Buster
- Orbit defenders
- Orbit Drift - Space Explorer