Ben Whiting reviewedPlanywayGoogle Calendar inside your Trello
 Recommended
Pros: 

best tool of its kind I've found: organize the work with Trello; schedule time for the work with Planyway

Cons: 

only available in the web app currently; requires Trello (for better or worse)

I spent over a year looking for an app that could do this. I had settled on Trello and been scheduling blocks of time on paper, when I found Planyway. The ease of drag and drop (re)scheduling and custom blocks of time was exactly what I wanted, and two-way sync with Google Calendar made those blocks of time visible and editable anywhere. Fantastic tool

Ben Whiting has used this product for one month.