SocialQuest is an add-on to assist groups of questing players coordinate. SocialQuest allows other SocialQuest users in your Party/Raid/Battleground to receive on screen messages whenever selected quest events occur. Also you may have SocialQuest broadcast quest events into your party/raid/battleground chat, as well as guild and/or a custom channel that you specify. The channels (if any) that get broadcast on and which events get broadcast, are completely configurable. SocialQuest will also allow receipt/broadcast of when other SocialQuest users begin/stop following you, or when you follow them. This can be handy if your friend is following you and you want to know if they get hung up on something behind you.
SocialQuest currently supports the following quest events:
abandon = triggered when a quest is abandoned
complete = triggered when a quest is turned in
fail = triggered when a quest is failed
finish = triggered when all of a quest's objectives are completed
accept = triggered when a quest is accepted
progress = triggered when the status of a quest objective changes

I realize most people will not wish to broadcast event updates to raid/battleground/guild channels, and because of this, these options are turned off by default. The custom channel option allows a group (guild or maybe just friends) to choose a common channel to join and broadcast quest events to (this is nice since it offers an opt-in style of notifications).

NOTE: SocialQuest depends on the Ace3, AceQuest and Sea libraries to function, so these must also be installed (the Readme includes instructions for this)