I've been using Optinly for a while now and I love it! It's a great popup management tool for websites, which is easy to integrate and maintain and has lots of targeting options, beautiful templates, and a bunch of possibilities to display the popups based on user interaction with your site.

The only thing I would like to see is the ability to insert my own HTML into it, to build completely custom by my own. There was teased a release of an easy to use custom popup builder, but its not clear, when and if this will be released. Other than that, it's an amazing tool and I will love to use it for me and my clients!