WARNING: I am not an expert of Spring Boot. There are a lot of things that I find really interesting about it and of course that can really improve your day-to-day work. Moreover I don't have anything against Spring Boot nor people who develop it or use it. But I think that community are overestimating/overvenerating this product.
A year ago I started to receive a lot links about blogposts, tweets, information about Spring Boot. From his website you can read:
Spring Boot makes it easy to create stand-alone, production-grade Spring based Applications that can you can "just run".
And it seems that this thing has just revolutionized the Java world.