With just a few simple steps, Anypoint by MuleSoft enables you to manage users, monitor and analyze traffic, and secure APIs with ordered policies. It provides API management for every connection made to backend services and data sources with Mule runtime engine, a single runtime deployable as an integration engine and an API gateway. Wherever your APIs are hosted and whatever technologies they run on, API Manager lets you keep tabs on the APIs in your application network from one place.
Both 3scale and Apiary are great tools for managing APIs. 3scale has some great features to offer such as log tracking, single sign-on, custom branding, analytics etc. 3scale has two plans - a Pro plan that is priced at $750 perAPI Management Services