Nice overview of how iMessage security works, in a way that not even Apple can intercept messages. Interesting in view of WhatsApp's recent announcement of encryption and all the FBI / hacking hoopla.
So this unofficial app is available for Android. It allows you to use Apple's iMesage service. Cool, right? It's a security disaster: A user installs it, and types in their Apple ID account information. This goes to a server in China which stores it and spoofs (fakes) an iMac connected to iMessage using the credentials. So it allegedly works. But you are giving your Apple ID password to an unknown entity in China. Your Apple ID is very likely tied to an iTunes account, which is very likely tied to your credit card. Oh, and this app can also install any software on your phone without your permission. Google and Android do nothing to protect the average user. Yet the average user is not a computer security expert with perfect judgement. This is where Apple's App Store rules and tight security shines through. It protects the average user from their own ignorance. And that's a good thing because not all users can be expected to be experts before getting a smartphone.