The ability to quickly prototype without having an actual backend server available, as well as being able to use it with Java 8 Lambdas! It's still fairly new so I don't know all of its features yet (but they are coming). As far as what I've seen thusfar, it seems like this would work really great if you were working on something that was heavily data driven - such as a mobile app where you need fast access to lots of rows/records at once. We're using Jasdb within our React Native application. Once we had everything up and running there wasn't much left to do other than add some more endpoints / API methods into the existing ones that already existed in react native.