| Solution | Company | Type | Offline Support | Self-hosted Sync | Decentralized Sync | Database | Type of DB | OS/Platforms | Languages | Open-Source Component | License | Remarks | Country |
| Couchbase (Lite + Couchbase Sync Gateway) | Couchbase (a merger of Couch One and Membase) | Online | ✅ | The CE Sync is a bare minimum and typically not usable; Self-hosted Sync with Couchbase Servers is available as part of their Enterprise offering | ✅ as part of the Enterprise offering; gets expensive quickly | Edge: Couchbase Lite; Server: Couchbase | Multi-model NoSQL document-oriented database | Couchbase
Lite: iOS, Android, macOS, Linux, Windows, Raspbian Couchbase Sync Gateway: Red Hat Enterprise Linux (RHEL) 9.x, Alma Linux 9.x, Rocky Linux 9.x, Ubuntu, Debian (11.x, 12.x), Windows Server 2022 |
.Net, C,
Go Java, JavaScript, Kotlin, PHP Python, Ruby, Scala |
✅ | Couchbase Lite is available under different licenses; the open source Community Edition does not get regular updates and misses many features especially around Snyc (e.g. it does not include Delta Sync making it slow and expensive) | Typically requires Couchbase servers, quickly gets expensive | 🇺🇸 |
| Firebase | Google (Firebase was acquired by Google in 2014) |
Online | Local cache only, no persistence, syncs when online | ❌ | ❌ | Cloud: Firebase Realtime Database; Edge: Only caching, no DB (called Firestore) | Document store | iOS, Android, Web | Java, JavaScript, Objective-C, Swift, Kotlin, C++, Dartlang,
C#, Python, Go, Node.js |
❌ | proprietary | Tied to Google Cloud, requires internet connectivity | 🇺🇸 |
| MongoDB Realm + Atlas Device Sync | MongoDB (Realm was acquired by MongoDB in 2019) |
Offline-First | ✅ | Cloud-based sync only | ❌ | Cloud: MongoDB, Edge: Mongo Realm DB | MongoDB: NoSQL document store; RealmDB: Embedded NoSQL DB | MongoDB: Linux OS X Solaris Windows Mongo Realm DB: Android, iOS |
more than 20 languages, e.g. Java, C, C#, C++ | ✅ | MongoDB changed its license from open source (AGPL) to MongoDB Inc.'s Server Side Public License (SSPL) in 2018. RealmDB is open source under the Apache 2.0 License. The Data Sync was proprietary. | Deprecated (in Sep 2024); End-of-life in Sep 2025; ObjectBox offers a migration option | 🇺🇸 |
| ObjectBox Sync | ObjectBox | Offline-first | ✅ | ✅ | In development | ObjectBox | Object-oriented embedded NoSQL DB | Android, Linux, Ubuntu, Windows, macOS, iOS, QNX, Raspbian, any POSIX system really, any cloud (e.g. AWS/Azure/Google Cloud), bare metal |
C, C++, Java Kotlin, Swift, Go, Flutter / Dartlang, Python |
✅ | DB: Open source bindings, Apache 2.0, closed core | Highly efficient (saves CPU, Memory, battery, and bandwidth); fully offline-first, supports on-premise settings, 100% cloud optional | 🇩🇪 |
| Supabase | Supabase | Online | Limited | ✅ | ❌ | Cloud DB: PostgreSQL | Relational document store | Primarily a cloud solution | JavaScript/TypeScript Flutter/Dartlang, C# Swift, Kotlin, Python |
✅ | Apache License 2.0 | Supabase is mainly designed as a SaaS, for use cases with constant connectivity | 🇸🇬 |