MongoDB Realm Has Arrived

MongoDB Realm helps you build modern mobile apps, faster. Use the Realm Mobile Database alongside Realm Sync (beta) to keep app data up-to-date in real time across multiple users, devices, and the MongoDB backend. Stop worrying about network availability and focus on building offline-first apps, with the innovative features your users will love.


Realm helps companies build engaging mobile applications with minimal development time. Learn why every day hundreds of thousands of developers choose Realm.

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Realm Platformを利用すると、双方向のデータ同期やリアルタイムの共同編集といった複雑な機能を持ったアプリを短期間に作れるようになります。浮いた時間はサービスの本質的な機能の開発に使えます。

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Realm Database

Use the Realm Database to save data in minutes so you can build mobile apps in a fraction of the time. Our object database is a simple alternative to SQLite and Core Data and proudly open source. Available for Java, Swift, Objective‑C, JavaScript, and Xamarin.

class Dog {}

Dog.schema = {
  name: 'Dog',
  properties: {
    name: 'string',
    age: 'int',

let realm = new Realm();
realm.write(() => {
  realm.create('Dog', {name: 'Rex', age: 1});

let pups = realm.objects('Dog').filtered('age < 2');
@interface Dog : RLMObject
@property NSString *name;
@property NSInteger age;
@implementation Dog

Dog *dog = [Dog new]; = @"Rex";
dog.age = 1;

RLMRealm *realm = [RLMRealm defaultRealm];
[realm transactionWithBlock:^{
  [realm addObject:dog];

RLMResults<Dog *> *allDogs = [Dog allObjects];
RLMResults<Dog *> *pups = [allDogs objectsWhere:@"age < 2"];
class Dog: Object {
  @objc dynamic var name = ""
  @objc dynamic var age = 0

let dog = Dog() = "Rex"
dog.age = 1

let realm = try! Realm()
try! realm.write {

let pups = realm.objects(Dog.self).filter("age < 2")
public class Dog extends RealmObject {
  public String name;
  public int age;

Dog dog = new Dog(); = "Rex";
dog.age = 1;

Realm realm = Realm.getDefaultInstance();

RealmResults<Dog> pups = realm.where(Dog.class)
                               .lessThan("age", 2)
public class Dog : RealmObject 
  public string Name { get; set; }
  public int Age { get; set; }

var realm = Realm.GetInstance();
realm.Write(() => 
  realm.Add(new Dog
    Name = "Rex",
    Age = 1

var pups = realm.All<Dog>().Where(d => d.Age < 2);

Realm Platform

Deploy data sync for your mobile apps use Realm Database and create reactive app experiences in as little as 10 lines of code. Realm Object Server and Realm Database combine to make the Realm Platform.

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// Authenticating the User
[RLMSyncUser logInWithCredentials:[RLMSyncCredentials credentialsWithGoogleToken:@"google token"]
                    authServerURL:[NSURL URLWithString:@""]
                     onCompletion:^(RLMSyncUser *user, NSError *error) {
  if (user) {
    // Opening a remote Realm
    NSURL *realmURL = [NSURL URLWithString:@"realm://"];
    RLMRealmConfiguration *config = [[RLMRealmConfiguration alloc] init];
    config.syncConfiguration = [user configurationWithURL: realmURL];
    RLMRealm *realm = [RLMRealm realmWithConfiguration:config error:nil];
    // Any changes made to this Realm will be synced across all devices!
  } else if (error) {
    // handle error
// Authenticating the User
SyncUser.logIn(with: .google(token: "google token"),
               server: URL(string: "")!)
{ user, error in
  if let user = user {
    // Opening a remote Realm
    let realm = try! Realm(configuration: user.configuration())
    // Any changes made to this Realm will be synced across all devices!
  } else if let error = error {
    // handle error
// Authenticating the User
User user = User.login("google token"),
// Opening a remote Realm
String realmURL = "realm://";
Realm realm = Realm.getInstance(user.getDefaultConfiguration());
// Any changes made to this Realm will be synced across all devices!
// Authenticating the User
Realm.Sync.User.registerWithProvider('', 'google', googleAccessToken, (error, user) => {
  if (!error) {
    // Opening a remote Realm
    var realm = new Realm({
      sync: {
        user: user,
        url: 'realm://',
    // Any changes made to this Realm will be synced across all devices!
var user = await User.LoginAsync(Credentials.Google("google token"),
                                 new Uri(""));

var realmUrl = new Uri("realm://");
var realm = Realm.GetInstance(user.configuration());
// Any changes made to this Realm will be synced across all devices!

Read a Whitepaper

Learn about Realm's best practices, approach to identity, access control, auditing and logging and encryption. Check out some of our whitepapers below.

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Try a Demo

Learn how to get a synchronized Realm up and running with just 20 lines of code, and discover the power of server-side event handling in a simple demo.

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Thread Learningはデジタルネイティブ世代に教育を提供しています

Realm Platformを用いた複数デバイス間のリアルタイムのデータ同期により、特別支援教育のチームはケアプランを綿密に調整できます。詳しくはこちらをご覧ください。

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Arccos Golfは試合中に必要な情報を即座に届けます


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Realm Platformのデモアプリケーションとデベロッパーエクスペリエンスをご覧ください





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