What is the advantage of Mendeley over Zotero?

My understanding is that Zotero implements essentially all of Mendeley's features, and is free and open-source. (Here's the comparison according to Mendeley: https://www.mendeley.com/compare-mendeley/ ). I think most people just haven't heard of it. It's supported and developed by a foundation, and if you ever stop liking it you can take all your data and move it to Mendeley very quickly. On the other hand, I don't think it's easy to leave Mendeley: https://feedback.mendeley.com/forums/4941-general/suggestion...

EDIT: Here's how Docear compares them: http://www.docear.org/2014/01/15/comprehensive-comparison-of... Zotero lacks Android/iOS apps (except for Zandy on Android, which is poor).