If you ask any long-time iPhone owner about iMessage, they will answer that it is a great addition to their Smartphone. No longer did they need to worry about how much it would be to text someone overseas. If they had an iPhone and a data connection (cellular or Wi-Fi) then they could message each other for free in the same conversation thread as their SMS messages. Seamlessly your phone would switch between SMS and iMessage, choosing blue or green speech bubbles, depending on the best way to deliver a message.
Apple weren't first to market with this concept, for years Blackberry ran it's BBM service, but Apple did what Apple does best - make it 'just work' and market it to the masses.
Of course, if your friends didn't own an iPhone they couldn't take advantage of this feature, sometimes leading to awkward social situations if you happened to be 'Green'.
In 2011, Microsoft purchased Skype for a staggering $11bn, and some in the industry wondered if they had made the right decision - Microsoft already had an Instant Messaging platform for the masses and the Lync Communicator platform for businesses, why would it need another VoIP or messaging system?
With Windows 10 we see the fruits of this work, in particular on Mobile where we see the new Messaging app integrate Skype directly. Voice or Video calls can be initiated via the app and all conversations can be synced between mobiles, tablets and PCs and works in a similar fashion to Messages on Mac OS X.
Microsoft's new Messaging app will allow you to send group texts, chats and calls when it is available later this year - it won't be in the new Technical Preview build available next week - and has several things going in it's favour that iMessage cannot offer. Skype is available cross platform: Android, iOS and Windows users will all be able to take advantage of the group messaging to all your friends - even on Smart TV's, BluRay players and every Linux, Mac and Windows device on which Skype can run today.
Hopefully this can help avoid social Green or Blue friend issues when it comes to messaging.