- Oggy and the Cockroaches !
- Oh C.R.A.P.!
- Oh My Eyes!
- OH! Shapes: A Chain Match Game
- Oh!Natto! ~納豆ネバネバシミュレーション~
- Ohana Island
- OhSnow
- Oil Paint Art Color By Numbers
- Oil Painting - Color By Number
- Oil Plumber City Plus
- Ojibwe Game
- Ojo Rojo
- OK Golf
- Okey Rummy
- OKO
- OkuDoku Number Brain Challenge
- Old Castle Escape
- Old Macdonald Had A Farm Game
- Old Man's Journey
- Old Museum : Detective Case
- Old-School Snafu
- Old-School Snafu
- Olim bola
- Olimdal
- OLLAPSE - Block Matching Game
- Olodo
- OLYM
- OM Nom Puzzle
- Omar & Hana
- OMBY
- OMG-WOW +FUN
- Omino!
- Ominous Objects: Lumina Camera HD - Hidden Objects
- Ominous Objects: Trail of Time HD
- OMJ - Oh My Jokes
- On the line
- On-Core Sudoku
- On-Core Wordfind
- ON/OFF
- Once Upon A Match
- ONCE fandom TWICE
- One - Touch - Draw
- One Block Sudoku
- One Block: Puzzle Adventure
- One Connect Puzzle
- One Digit Field
- One digit is fake
- One Level 2 Stickman Jailbreak
- One Level 3 Stickman Jailbreak
- One Level: Stickman Jailbreak
- One Life Story
- One Line - 1 Touch Brain Game
- One Line - Connect the dots
- One Line - Fill with one line
- One Line 3D
- One Line : Connect Points
- One Line Block Puzzle
- One Line Coloring
- One Line Connect - Brain Game
- One Line Dot Connection
- One Line Dots - Brain Puzzle