The ability to have an inbound queue for our web applications and outbound queues for our mobile apps. The integration with other services like Slack and Twilio makes it easy to use. There's nothing I dislike about IronMQ. If you're looking for a simple messaging solution that can scale horizontally, this is the one for you. We've been using IronMQ as part of our continuous delivery pipeline for several years now. It has made it much easier to build new features quickly and easily without having to worry about scaling issues.