# ObjectBox — Superfast On-Device Database for Mobile and IoT

> ObjectBox is a high-performance embedded database optimized for mobile, IoT, and edge devices. It offers object persistence with minimal CPU and memory usage, plus built-in data sync for offline-first apps.

## Install

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# ObjectBox — Superfast On-Device Database for Mobile and IoT

## Quick Use
```java
// Android/Java example
@Entity
public class Task {
    @Id public long id;
    public String title;
}
BoxStore store = MyObjectBox.builder().androidContext(context).build();
Box<Task> box = store.boxFor(Task.class);
box.put(new Task(0, "Buy groceries"));
```

## Introduction
ObjectBox is an embedded NoSQL database designed for on-device storage where speed and resource efficiency matter. It stores objects directly without SQL mapping overhead, achieving read/write speeds significantly faster than SQLite on constrained hardware. Built-in data sync enables offline-first architectures across mobile and edge deployments.

## What ObjectBox Does
- Persists objects directly with zero-copy deserialization for minimal latency
- Runs on Android, iOS, Linux, Windows, and macOS with tiny footprint
- Provides reactive queries that notify observers when data changes
- Includes ObjectBox Sync for peer-to-peer and client-server data synchronization
- Supports vector search for on-device AI similarity queries

## Architecture Overview
ObjectBox uses a custom storage engine built on memory-mapped files with a B+ tree variant optimized for object access patterns. Objects are serialized using FlatBuffers, enabling zero-copy reads directly from mapped pages. The database operates fully ACID with multiversion concurrency control (MVCC), allowing lock-free reads concurrent with writes. Code generation at compile time creates binding classes that eliminate runtime reflection.

## Self-Hosting & Configuration
- Add the Gradle plugin (Android) or CocoaPods/SPM (iOS) dependency
- Define entities with `@Entity` annotations; the code generator handles the rest
- Database files are stored in the app sandbox by default; path is configurable
- ObjectBox Sync server can be self-hosted for fleet-wide data synchronization
- Configure max database size and read-only mode via BoxStoreBuilder options

## Key Features
- Sub-millisecond CRUD operations on resource-constrained devices
- ACID transactions with MVCC for safe concurrent access
- Cross-platform: same API concepts on Android, iOS, Flutter, Go, Python
- Built-in vector search for on-device embeddings and similarity matching
- Data Sync works offline and resolves conflicts automatically

## Comparison with Similar Tools
- **SQLite/Room** — SQL-based with ORM overhead; ObjectBox is object-native and faster for CRUD
- **Realm** — Similar object DB but heavier runtime; ObjectBox has smaller binary size
- **Hive (Flutter)** — Lightweight key-value only; ObjectBox supports relations and queries
- **WatermelonDB** — React Native lazy-loading DB; ObjectBox offers broader platform support
- **LevelDB** — Low-level key-value store without object mapping or sync

## FAQ
**Q: Is ObjectBox free for commercial use?**
A: The database itself is free under the Apache 2.0 license. ObjectBox Sync is a separate commercial product.

**Q: How does it compare to SQLite in speed?**
A: Benchmarks show ObjectBox performing CRUD operations significantly faster than SQLite, especially for bulk operations on mobile.

**Q: Does it support Flutter?**
A: Yes, there is an official ObjectBox package for Dart/Flutter with the same performance characteristics.

**Q: What about data encryption?**
A: ObjectBox supports database-level encryption to protect data at rest on the device.

## Sources
- https://github.com/objectbox/objectbox-java
- https://docs.objectbox.io

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Source: https://tokrepo.com/en/workflows/objectbox-superfast-device-database-mobile-iot-a3ed1e5a
Author: Script Depot