What are some alternatives?
When comparing Apiary and Postman Collections, you can also consider the following products
Gravitee.io - Gravitee.io is a flexible, lightweight and an open source API management solution.
DreamFactory - DreamFactory is an open source REST API backend for mobile, web, and IoT applications.
Apigee - Intelligent and complete API platform
Paw - Paw is a REST client for Mac.
Django REST framework - Django REST framework is a toolkit for building web APIs.
AWS CloudTrail - AWS CloudTrail is a web service that records AWS API calls for your account and delivers log files to you.