When comparing ShareLaTeX vs Authorea, the Slant community recommends ShareLaTeX for most people. In the question“What are the best online LaTeX editors?” ShareLaTeX is ranked 1st while Authorea is ranked 4th. The most important reason people chose ShareLaTeX is:
Several colleagues can work simultaneously on the same document, remotely from each other.
Question Ranking
Pros
Pro Simultaneous collaboration
Several colleagues can work simultaneously on the same document, remotely from each other.
Pro Version history
As an online editor, ShareLaTeX keeps track of document versions and what has changed from one version to the next. Reviewing edit history is easy, as is reverting back to an older version if needed.
Pro Submit articles directly to journals
Authorea has a Direct Submission feature, that allows authors to directly submit their work to several academic journals, with the correct formatting.
Pro Real-time collaboration
Ability to edit in real-time like Google Docs.
Pro Get a DOI to make your work citeable
You can post a preprint or make your draft public on Authorea, and request a DOI. Having a DOI means your work is citable on e.g. Google Scholar. Because it mints DOIs, Authorea is a good venue for privately writing and publicly posting preprints, research plans, and finished papers.
Cons
Con Users need to pay to access all the features
Even though there is a free plan, features such as collaborative work and synchronization with services like Dropbox or GitHub are only available on the paid plans.
Con Not completely free
Authorea can be used with a free plan, but to get the complete set of features, a paid subscription plan is needed.