- Op reis in de ruimte!
- Op safari naar Afrika met Dirkje - Juf Jannie leest voor
- Opacha-mda
- Opart
- Opdoku = Calcudoku + Mathdoku
- Open 100 Doors - Christmas!
- Open 99 Doors
- All Lit
- Open Bigger Surprise Capsule
- Open Case Simulator
- Open Door - Escape Games
- Open Door Night
- Open Face Chinese Poker (OFC)
- Open Giant Surprise Puppycage!
- Open Gifts Simulator
- Open House Hidden Object Games
- Open House: Meet Friends
- Open It!30 Doors
- Open One Photo
- Open One Photo Plus
- Open Puzzle Box
- Open Road For King Puzzle
- Open Sorcery
- Open Test
- Open Test
- Open The Classic Door
- Open The Classic Door Season 3
- Open the Lock!
- Open the Way 3D
- Open Train Tycoon Deluxe
- Open World Delivery Simulator
- Open World Driver - Taxi 3D
- Open World Madout Mafia City
- OpenD6 Toolkit
- Opening day of a fresh baker’s
- OpeningTree - Chess Openings
- OpenLitterMap
- OpenSaury
- Open the door - fun games
- OpenYour
- Opera Maker
- Operation: ATAK
- Operation: ANKA
- Operate Now: Hospital
- Operate Snow Excavator Crane
- Operation Ares - A Revolution on Mars! Recruit Spies, Complete Missions, & Gain Independence
- Operation Calculus
- OPERATION DRACULA
- Operation Dracula X
- Operation February
- Operation Helix
- Operation Mindfall 2.0
- Operation Optics
- Operation Outbreak
- Operation Santa
- Operation Smoochy
- Operation wow HD
- Operation: New Earth
- Operation: Survive Runner 3D
- OperationAntiVirus
- Operators - Math Exercises
- Operação Abaporu
- Opernice
- Ophidia
- Opi viittomaan
- Opinion Game
- OpinionGames: Nuclear phase-out
- OpinionGames: Gotthardsanierung (Archiv)
- Oportuno Beyond Infinity Pills Game HD
- Opp Ball