| Oogli LLC | 🍎 | 1 | 4.5★ | Music |
| Oola Bowls Franchising LLC | 🍎 | 1 | 5.0★ | Food & Drink |
| Ooni Limited | 🍎 | 1 | 4.8★ | Food & Drink |
| Oops Finance, Inc. | 🍎 | 1 | 3.7★ | Finance |
| OopsFactory | 🍎 | 1 | 4.3★ | Photo & Video |
| Ooredoo Kuwait | 🍎 | 1 | 4.6★ | Utilities |
| Ooredoo Myanmar Limited | 🍎 | 1 | 3.6★ | Productivity |
| Oosthuizen Booyse and Associates Incorporated | 🍎 | 1 | — | Business |
| OpConnect, LLC | 🍎 | 1 | 3.7★ | Navigation |
| OpSoft | 🍎 | 1 | 5.0★ | Navigation |
| OpStack AI | 🍎 | 1 | — | Business |
| Opal Limited | 🍎 | 1 | 4.8★ | Music |
| Opal OS | 🍎 | 1 | 4.8★ | Productivity |
| Opay Pty Ltd | 🍎 | 1 | — | Utilities |
| Opcity, Inc. | 🍎 | 1 | 4.9★ | Business |
| Open Co Tecnologia S.A | 🍎 | 1 | 4.4★ | Finance |
| Open Dating Media LTD. | 🍎 | 1 | 4.5★ | Social Networking |
| Open Education, LLC | 🍎 | 1 | 4.7★ | Education |
| Open Inc. | 🍎 | 1 | 4.9★ | Health & Fitness |
| Open Internet Foundation | 🍎 | 1 | 4.8★ | Social Networking |
| Open Knowledge Association Ltd. | 🍎 | 1 | — | Education |
| Open Mind Developments Corporation | 🍎 | 1 | 4.8★ | Lifestyle |
| Open Play | 🍎 | 1 | 4.0★ | Sports |
| Open Sky New Media Limited | 🍎 | 1 | — | REFERENCE |
| Open Text Inc. | 🍎 | 1 | 4.4★ | Productivity |
| Open Transit Software Foundation | 🍎 | 1 | 2.8★ | Navigation |
| Open Vision Engineering, Inc | 🍎 | 1 | 4.8★ | Utilities |
| Open house finder llc | 🍎 | 1 | 4.1★ | Business |
| Open to the Public Investing, Inc. | 🍎 | 1 | 4.7★ | Finance |
| OpenClassrooms | 🍎 | 1 | 4.8★ | Education |
| OpenCloud GmbH | 🍎 | 1 | 5.0★ | Utilities |
| OpenCourt, Inc. | 🍎 | 1 | — | Sports |
| OpenEM Foundation | 🍎 | 1 | 4.8★ | Medical |
| OpenEvidence Inc. | 🍎 | 1 | 4.9★ | MEDICAL |
| OpenGames LLC | 🍎 | 1 | 4.9★ | Games |
| OpenLink Software Bulgaria AD | 🍎 | 1 | — | Travel |
| OpenLink Software Inc. | 🍎 | 1 | 5.0★ | Social Networking |
| OpenMind AI, Inc. | 🍎 | 1 | — | Health & Fitness |
| OpenPhone Technologies Inc | 🍎 | 1 | 4.5★ | Business |
| OpenRemote | 🍎 | 1 | — | Productivity |
| OpenRhapsody | 🍎 | 1 | — | Lifestyle |
| OpenSooq | 🍎 | 1 | 4.6★ | Shopping |
| OpenSports Inc. | 🍎 | 1 | 4.9★ | Sports |
| OpenVPN Inc. | 🍎 | 1 | 4.8★ | Utilities |
| OpenWardrobe, Inc. | 🍎 | 1 | 4.2★ | Lifestyle |
| OpenWeb Technology Corp. | 🍎 | 1 | — | News |
| Openbank S.A. | 🍎 | 1 | 4.4★ | Finance |
| Openbuy开买科技 | 🍎 | 1 | 3.9★ | Shopping |
| Opendoor Labs, Inc. | 🍎 | 1 | 4.8★ | Lifestyle |
| Opendream | 🍎 | 1 | 4.5★ | Health & Fitness |