Invite is the latest single-purpose Microsoft app for iOS, and it's designed to let you set up small events and group meetings with ease and across organizations. You sign up with any email address, and Invite then lets you create an event, invite anyone from your email account's address book, and pick times that the entire group can vote on. Once settled, it shows up in everyone's respective calendars. It's designed to make settting up meetings between employees of different companies a bit easier, as neither party can usually see one another's calendar.
The app is another aesthetically pleasing take from Microsoft, which has upped its mobile design game in the last couple of years with its Office for iOS suite and a handful of other iOS and Android products. Invite is quick and easy to navigate and brings new meaning to the descriptor "no frills," as it has almost zero extraneous features or functions outside of its core purpose.

Of course, Microsoft's chops in the app development department are thanks in part to a series of clever acquisitions to help the company gain an edge on competing mobile platforms. Those include the Sunrise calendar app, which Microsoft purchased back in February, as well as Acompli, the mobile email client Microsoft acquired in December and rebranded as Outlook. And in June, Microsoft scooped up German software startup 6Wunderkinder GmbH, maker of the to-do list app Wunderlist.
Another experimental Garage project that may or may not take off
Invite is different because it was developed in-house, by what the company calls the Microsoft Garage. The group is a collective of interns, designers, engineers, and other Microsoft employees across all facets of the company that riff on new ideas and put them out in the wild early to gain feedback. The Microsoft Garage is responsible for Send, a conversational no-frills email app that's intended to turn the communication variant into a version of texting. Invite looks in part based on Tossup, an app the Garage released back in June to help friends make evening plans. These apps don't tend to be blockbuster successes; rather, they appear to be a creative outlet for employees to work outside the confines of the standard Microsoft environment.
As with most Garage apps, Invite is only available at the moment for iOS in the US and Canada. Microsoft says Android and Windows Phone versions will be out some time in the future.