Do NOT create a new mobile app. Integrate with Groups App instead.
Do not fragment the mobile app space. Do NOT create a new app of Planner. Use Groups App to integrate instead.
There already is a mobile app for Office 365 Groups. And Planner plans have a direct relationship with Groups. It would be great if Planner is integrated into that existing app. Groups app will have conversations, Files, Notebook, Calendar, and Plans.
Would be great if the apps worked together and had key features. Example: the Group app allows you to tag individuals and see the group’s calendar and one notebook. However, in the Groups app, you can’t connect to the updates from Planner to the actual Planner task. The Planner app does not have tagging or ability to see calendar/one note book. The Teams app has a calendar, but it’s not the group calendar, and allows you to see the teams chat.
Basically, all the apps have strengths, but they are too disconnected, so to perform basic functions, I’m bouncing between various applications.
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Matthias Mitze commented
Great idea, because currently I see in the Groups app only the conversation, but cannot edit tasks
opposite to this idea "Provide a mobile app" https://planner.uservoice.com/forums/330525-planner-preview-feedback-forum/suggestions/11130210-provide-a-mobile-app