Datastore was initially designed for use from App Engine, i.e., an easy start, no management, automatic scaling environment ("serverless" to use the current in-

Datastore was initially designed for use from App Engine, i.e., an easy start, no management, automatic scaling environment ("serverless" to use the current in-vogue term). I would view the Firestore API as a further extension (the "Datastore Mode" functionality was always an element of the design) of that paradigm, extending to the case where you have no trusted piece of code to mediate requests to the database, thus allowing direct use from, e.g., mobile apps (at which point other issues such as disconnected operation surface). So not so much a "different kind of product" and more a product that supports a strict superset of use cases.