Realm

Realm Sync. For reactive, run-anywhere mobile apps.

Keep your data up-to-date across devices, users, and your back end with Realm Sync. Facilitate development and ensure performance in any situation.

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A layer cake consisting of three layers: the bottom is dark green and labeled Atlas, the middle is bright green and labeled Realm Sync, and the top is a transparent green and labeled Realm Mobile Database.

Store locally and sync globally with MongoDB Realm. With out-of-the-box conflict resolution and networking code, Realm Sync reduces build time while keeping your apps performant and responsive.

A semicircle of two bidirectional arrows linking a blue and green smartphone with a bright green data document.

A shortcut for building real-time sync

Speed up and simplify development. Realm Sync takes care of complexities like error handling, cuts down the amount of required code by 20% or more, and streamlines your application architecture — freeing you up to dream big and build boldly.

A visual representation of a database atop a smartphone. In the background are two clouds and two bidirectional, circular arrows.

Run your apps anywhere

Ensure consistent data and a smooth experience wherever your users may be. Realm Sync bridges the gap between local storage (provided by Realm Mobile Database) and your back end (provided by MongoDB Atlas) to keep data current and accurate.

A green hand taps a smartphone. Immediately above is an icon that says “Auto-Scale,” and to the right is a chart with a cloud at the bottom and a green arrow pointing to the top.

Auto-scale with ease

Built on a serverless architecture, Realm Sync seamlessly auto-scales to support spikes in user demand. In addition, Realm Sync supports MongoDB Atlas’ global, multi-cloud clusters for increased versatility and flexibility.

Feature overview

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Built-in conflict resolution

Ensure data uniformity by merging changes through operational transformation.

Lightweight, local data storage

Store data on devices with the Realm Mobile Database — and sync with Atlas when connected.

SDKs for any platform

Build apps for any platform, from iOS to Android to .Net or Node.js, without sacrificing user consistency.

Best-in-class privacy and security controls

Encrypt your data in-flight, at-rest, in the cloud, or on your device.

Store + sync data — anywhere

MongoDB Realm Sync is for modern mobile applications with a global user base. Overcome distance and dead zones to keep your apps running and your users happy — under all conditions.

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Data sync with less effort

Trim time (and lines of code) with easy-to-use Realm Sync. Keep your app data and user changes consistent across devices and back ends with automatic conflict resolution.

Seamless back end integration

Plug into a scalable, serverless back-end powered by MongoDB Atlas. Outsource infrastructure logistics, auto-scale with user demand, and never worry about standing up servers (or surprise bills) again.

Data sync with less effort

Trim time (and lines of code) with easy-to-use Realm Sync. Keep your app data and user changes consistent across devices and back ends with automatic conflict resolution.

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