Ease of use
Is it pretty, powerful or an email eyesore?
The prettiest, simplest app here is Unibox: it’s like no email program you’ve ever used, and we mean that in a nice way. Grabbing contact icons from Gravatar and from their email domain is a particularly nice touch.
Mailbox comes a close second with its eminently swipeable interface. It’s prettier than Airmail 2, which offers more on-screen options and can feel a little crowded as a result - although not as crowded as Thunderbird, which feels dated and overly cluttered. Thunderbird isn’t hard to use, but it does feel like travelling back in time – and Postbox uses its engine but looks and feels much more like Apple’s Mail.
That leaves Outlook, which is vastly improved in its Office 2016 version: it manages to fit with Yosemite’s interface while being recognisably Microsoft, and it does a decent job of hiding its complexity if you don’t need it or want to see it. It doesn’t have the charm of Mailbox, but unlike older versions you don’t feel it’s been made by someone who’s never used a Mac either.
The prettiest, easiest to use app is Unibox. It’s more like Messages than email.