| Ongo Science Inc | 🍎 | 1 | 5.0★ | Health & Fitness |
| Oni Gaming | 🍎 | 1 | 4.8★ | Games |
| OnionCore LLC | 🍎 | 1 | 5.0★ | Health & Fitness |
| Oniri Inc | 🍎 | 1 | 4.6★ | Health & Fitness |
| Onkyo Corporation | 🍎 | 1 | 3.5★ | Music |
| Onlabs | 🍎 | 1 | 3.9★ | Education |
| Online Classifieds AG | 🍎 | 1 | 4.3★ | Lifestyle |
| Online Commerce Group BV | 🍎 | 1 | 4.0★ | Entertainment |
| Online Exchanges, LLC | 🍎 | 1 | 3.0★ | Shopping |
| Online Liquidation Auction LLC | 🍎 | 1 | 4.7★ | Shopping |
| Online Ordering | 🍎 | 1 | 5.0★ | Food & Drink |
| Online Permissions Technologies | 🍎 | 1 | 4.0★ | Utilities |
| Online Pilates Classes LLC | 🍎 | 1 | 5.0★ | Health & Fitness |
| Online Radio Box sp.z.o.o. | 🍎 | 1 | 3.9★ | Music |
| Online Reading Tutor Services Inc. | 🍎 | 1 | 4.0★ | Education |
| Online Security | 🍎 | 1 | 5.0★ | Utilities |
| Online Star Register | 🍎 | 1 | 4.6★ | Education |
| OnlineBookClub.org LLC | 🍎 | 1 | 2.8★ | Book |
| OnlinePizza Norden AB | 🍎 | 1 | 4.4★ | Food & Drink |
| Onloft Software LLC | 🍎 | 1 | 4.7★ | Developer Tools |
| OnlyDrams, LLC | 🍎 | 1 | — | FOOD_AND_DRINK |
| OnlyPapis, Inc. | 🍎 | 1 | 3.7★ | Lifestyle |
| Onne van Dijk | 🍎 | 1 | 4.8★ | BOOKS |
| Onnibank S.A | 🍎 | 1 | 4.6★ | Finance |
| Ono Management, LLC | 🍎 | 1 | 4.9★ | Food & Drink |
| Onoco | 🍎 | 1 | 4.7★ | Medical |
| Onomaly LLC | 🍎 | 1 | 4.0★ | Entertainment |
| Onout.Inc | 🍎 | 1 | 4.5★ | Shopping |
| Onpay Solutions Sdn Bhd | 🍎 | 1 | — | Business |
| Onrival LLC | 🍎 | 1 | 4.5★ | Health & Fitness |
| Onsen AI Limited | 🍎 | 1 | 4.9★ | Lifestyle |
| Onsite Analytics | 🍎 | 1 | 5.0★ | Utilities |
| Onsite Software | 🍎 | 1 | — | Business |
| Onskeskyen ApS | 🍎 | 1 | 4.8★ | Lifestyle |
| Onsoft SRL | 🍎 | 1 | 5.0★ | Productivity |
| Ontario Lottery and Gaming Corporation | 🍎 | 1 | 4.8★ | Lifestyle |
| Ontario Volleyball Association | 🍎 | 1 | 4.0★ | Sports |
| Ontaz Mobility Limited | 🍎 | 1 | 4.5★ | Music |
| Ontology Foundation | 🍎 | 1 | 4.0★ | Utilities |
| OntraQ.org | 🍎 | 1 | 4.9★ | Education |
| Ontrack Digital Sdn Bhd | 🍎 | 1 | 2.5★ | Shopping |
| Onur Hazar | 🍎 | 1 | — | Productivity |
| Onur Ince | 🍎 | 1 | 4.0★ | Medical |
| Onur Seref | 🍎 | 1 | — | Reference |
| Onur TASKIN | 🍎 | 1 | 4.3★ | Photo & Video |
| Onusoft Inc. | 🍎 | 1 | — | Music |
| Onward Care, Inc | 🍎 | 1 | 5.0★ | Travel |
| Onyx Games LLC | 🍎 | 1 | 4.7★ | SPORTS |
| Onyx Tech Inc | 🍎 | 1 | 4.6★ | Entertainment |
| Oobit Technologies | 🍎 | 1 | 4.4★ | Finance |