The good ol' days
A long time ago you needed separate programs for all instant messaging networks. One app for MSN, another app for Google Talk, a separate program for ICQ, another for AIM, and Skype chat only worked with the software from Skype.
Then came the multi-network clients. Trillian, GAIM, and Pidgin for PC. Nimbuzz, fring, Palringo, and many more for Symbian. Android and iOS got their fair share of multi-network IM apps too. They even got unified inboxes that brought your emails and SMSs together.
VoIP was always unified, because almost every VoIP operator uses the SIP standard. Except for Skype, but Nimbuzz and fring took care of that.
And then things fell apart
Somehow, someone turned back the clock. First, Skype got pulled from Nimbuzz and fring. Apparently because of a dispute over video calling, but normal calls and messages over Skype were yanked out too. Until Skype opens up again I suggest you don't pay a single penny for SkypeOut (use one of the many other VoIP services instead).
Fortunately Skype chat still works in imo, so you only need one instant messenger on your Android phone.
Or do you?
When AOL bought ICQ, they tried to axe their service from 3rd party clients in order to force-feed you their own app. Then came Blackberry Messenger. A great way to avoid the ridiculous SMS rates (the most expensive 140 bytes in the universe), but it only works on Blackberries. WhatsApp copied the ping app from Blackberry and brought it to Android and iPhone. And so did PingChat. And Kik Messenger and LiveProfile and Viber and KakaoTalk and GO Chat and many more. The app stores are full of single-network chat apps and they breed like rabbits.
The problem? All the new kids on the block use proprietary protocols that only work in their own apps. With so many networks your friends will be scattered all over the place. And with your friends scattered over MSN, WhatsApp, Skype, Kik, Viber, etcetera you'll need to fill an entire homescreen with apps that all do the same thing.
Some of these apps (like Viber) autostart without an option to switch it off. Others (WhatsApp) autostart and don't even have an exit button. They keep you available all the time, even when you want to take a break from messaging without shutting down your entire internet connection. They also upload your entire contacts list to their servers, even the contacts that you don't want to share. And if you want to stay connected, these apps and their background services take a large bite out of your RAM. Some even keep their processes alive if you sign out, if they let you sign out at all.
There is no multi-network program that connects the new IM/SMS hybrids into a single app. We're heading back to the dark ages of 1995 where every messenger required its own app.
Pick up the pieces
Urgently needed: one app to bind them all. Trillian, Nimbuzz, imo etc. did a great job unifying the old chat networks. The time has come to include the new messengers, and to force Skype back in line. This requires a bit of work from the multi-network app programmers, but that's not a big deal. They're more than willing to add networks to their apps. What holds them back is the lack of cooperation from Skype, WhatsApp, Viber et al. If the new networks stop being so anal retentive and publish some public APIs we'd have updated multi-network clients in a minute. At the very least the new networks shouldn't sabotage attempts to reverse engineer their protocols so that others can throw their networks into the mix.
WhatsApp, Viber, PingChat, Skype, Kik, KakaoTalk, GO Chat, LiveProfile: open up!
Bonus tip and abuse alert
Update: you can now unlink your phone number from within the Whatsapp app.