|Client API||Apache License, Version 2.0||Any||Free||Perpetual|
|Server||Personal License||Personal||Free||1 Year|
|Server||Commercial License||Commercial||800 GBP||1 Year|
Client API and Examples are licensed under Apache License, Version 2.0. License is perpetual.
This is the best option for integration HFS client libraries within your application, regardless from your purposes, application usage or its distribution model.
In short, personal usage means only assignee (a natural person) is allowed to access running server instance.
For more generic usage you may want to consider requesting server Commercial License.