SummitDB – NoSQL DB, Geospatial Index, Raft, Redis API and Fencing Tokens – v0.4.0

It's an in-memory database like Redis, so there's that limitation. A large dataset would require lots of ram.

It also runs over Raft, which makes it ideal as a primary data store, rather than a caching server. Though writes to Raft cluster will be slower than writing straight to a Redis server.

SummitDB is primarily a general purpose data store. You use it if you need to store various types of application data such as user records. It's aims to be a fast, durable, and consistent. It's kinda like Redis but with indexes and Raft.

Tile38 is specifically a geospatial/geofencing database. You use Tile38 if you have a traffic heavy proximity based application. It aims to be very fast at geo queries and geofence detection.