Recs.
Updated
Discord is a free voice and text communication platform targeted primarily at the gaming market. It aims to match the ease of use of existing chat clients like Skype and mix it with the power of servers with multiple rooms and role permissions offered by voice clients like Teamspeak.
SpecsUpdate
Pros
Pro Does not distunguish between free and paid users
Though Discord has a paid plan (Discord Nitro), it doesn't offer much of an advantage over using it for free — all users are treated the same way. They have maintained the fact that Nitro is just for users who wish to support them, and those who pay can customize their user experience better (e.g. animated avatars) and gets beta access to new features (e.g. addition of video calls).
Cons
Con Developer's previous company was sued for privacy violations, among other things
See:
http://classactionlawsuitsinthenews.com/class-action-lawsuit-complaints/openfeint-green-international-privacy-class-action-lawsuit-complaint/
https://www.ftc.gov/enforcement/cases-proceedings/closing-letters/openfeint-inc
Discord's privacy policy also states that while they might not sell your data, a company they get sold to will quite possibly attain said data and thus may be in "more" shady hands.