I have reviewed a variety of online task and project management tools. I have my biases, most notably a requirement for tight integration with gmail and google calendar, so my favorites are certainly slanted in this way. I created a spreadsheet to share what I have learned. Let me know if feature updates in any of these platforms need to be included in this 2016 snapshot.
I am currently using Gqueues because it works so well with google calendar and is easy to use. I wish it had better reporting features and a dashboard that summarized project progress, but who looks at that stuff in my field of work anyway?