Source - Vahid Rakhshan (2012), Letter Reliance of Scientific Publication on Citation Management Software: The New Generation, Journal of Dental Research, Dental Clinics, Dental Prospects
Mendeley is free-to-use, which is always a plus. It's also quite flexible and can be accessed from multiple devices and synchronizes across all the commonly used operating systems on desktop and mobile. It even has a web version.
It is also flexible in a different way. Mendeley's API is developed in a way that readily allows it to be integrated into other software for researchers, such as an online text editor like SciFlow.
Users of both SciFlow and Mendeley can now access their Mendeley Library from their text without having to alt-tab or undergo cumbersome select and apply processes for citing their from references. Simply connect your Mendeley to SciFlow and drag your references into the text. SciFlow will handle the formatting when you export your document.