Riak TS is focused to handle time series application needs. It can do fast read/write to IOT devices, there in is its strength. It also targets financial and economics data as well as in scientific research applications.
This is straight from Riak TS:
“Riak TS automatically co-locates, replicates, and distributes data across the cluster to achieve fast performance and high availability. The unique master-less architecture enables near-linear scale using commodity hardware so you can easily add capacity as your time series data grows.”