For work, or open source, or personal communications. What IM (not email) app do you have open all the time (Slack, Hipchat, hangouts, Gitter, etc.)? Why that one?
Slack for office and some random publicly available teams
FB Messenger and Viber for day to day with friends
Some friends use Hangouts so that comes in sometimes as well
Used to have Skype and WhatsApp but Im starting to cut down on all the attention killers. Also most of the day everything is muted except a few important channels or contacts. I only answer phone calls and come back to messages in spare time. If its important they should call me.