Using the new SharePoint Framework we are introducing a SharePoint Add-in for Office 365 Planner. You will now be able to manage your Planner tasks directly from your project site. I am looking for up to 10 organisations that are intrested in testing the Add-in. Please contact me should you be interested. You will recieve a one year free subscription up to 50 users.
The SharePoint wep part will allow you to do the follwoing. Actually for you who know about the iPlanner Pro for Outlook, it is almost the same functionality. http://planner.iglobe.dk/