azure is a big cloud player nowadays
slack is really, really, really great if you're a dev. the integration with apps is amazing. I get all notifications for my github repo pull requests/comments/branch creations in one channel, get pagerduty notifications in another channel, get ci pipeline notifications in third channel, have multiple multi-people chats/groups that are easily searchable and can hold all downloads, withc custom visibility....shyt is awesome as a dev work 'messenger'
I remember when I was using skype for business on multiple devices 5-6 years ago

shyt was trash