Mattermost 0.5.0 is a development “preview” release for sharing a first look at the Mattermost project outside the initial development team. This release is not recommended for production deployment and backwards compatibility of future versions and API stability is not guaranteed.
That said, multiple teams monitored by the Mattermost developers use the preview version for their core activities daily.
Release Candidates and Production Version
Supported Operating Systems and Browsers:
PC: Windows 7, Windows 8 (Chrome 43, Firefox 38, Internet Explorer 11)
Mac: OS 10 (Safari 7, Chrome 43)
Linux:Arch 4.0.0 (Chrome 43)
iPhone 4s and higher (Safari on iOS 8.3, Chrome 43)