Realm

Realm makes it easy to build modern reactive apps, realtime collaborative features, and offline-first experiences.

Realm (formerly tight.db) is a mobile database that enables its users to develop applications faster, develop applications that are fast, and craft amazing user experiences. Realm is a replacement for SQLite & Core Data. It can save users thousands of lines of code & weeks of work, and lets them craft amazing new user experiences. It is a Y Combinator company, headquartered in San Francisco.