Asopitech VS
Realm vs Alopex DB
Realm embedded mobile storage, its object model and the status of Device Sync, compared with Alopex DB.
Updated: Oct 13, 2026
What Realm is
Realm is a mobile database that runs directly inside phones, tablets and wearables. Its core component is written in C++ and used from SDKs for Swift, Kotlin, Dart, C++ and more.
How it works
- Object model: application objects are stored as they are, with no ORM.
- Local storage: data persists on the device disk, so apps work offline as well as online.
- Core component: every Realm SDK uses the same core database component.
Main features
- A mobile design that is careful with memory, disk space and battery.
- A local database for apps that work offline.
- Source code published under Apache-2.0.
Limits
MongoDB has announced the deprecation of Atlas Device Sync and the Realm SDKs. A version without sync features is published on the community branch. Moving data between devices or to a server is left to the application.
How it differs from Alopex DB
Both are embedded databases that run inside the application.
Alopex DB is a Rust database that grows from embedded to server to cluster on the same engine. It handles SQL, vector search, graphs and KV in one engine. The engine embedded on the device also runs as a server and a cluster, so the device and the server share the same data shape and SQL.
Choose Alopex DB as the home for mobile data, with the same engine from the device to the cluster. Start from the quickstart.