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It's Monday morning and Jack just realized that he has been meaning to have lunch with Kate and Bill for a while and they haven't been able to meet up. Jack and Bill work on the same project team, so their availabilities are similar, but because Bill doesn't respond to email frequently (despite the fact that he always has his smartphone with him), Jack has had trouble trying to schedule lunch the day of with Bill. Jack has also had trouble scheduling a lunch with Kate because he doesn't know her availability. Jack would like to have lunch with Kate and Bill sometime this week, the sooner, the better. Jack is able to take a one hour lunch between noon and 2pm on every day except Thursday when he has a conference call with the San Francisco office that lasts until 1:30pm.
Kate has been out of the office the past few weeks and has fallen out of sync with Jack. She has several meetings over the week, but none during lunchtime. She is excited to catch up with Jack and Bill.
In this scenario, Jack needs to create an event and invite Kate and Bill. Kate and Bill need to respond to the event.
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Other: The touch controls (swiping, scrolling, selection) are meant to be externally consistent with other applications and conventions on iOS and Android opertating systems.
Alternative Design directions
Inviting people: Aside from using an autocomplete field, it is possible to instead present a user with a list of all of their contacts as a combobox that allows multiple selection. We dislike this widget because it is not efficient for the case where users know whom to invite already. Some contacts lists my take 10s of screens on a mobile phone. It also would force the user into our mental model of presenting all contacts alphabetically where they may be thinking of them in other ways. Because of these drawbacks, we did not incorporate the combobox into our designs.