Apple likes to keep its own apps and services locked within its own ecosystem, with few exceptions – and iMessage isn't one of them. Well, one resourceful developer sought to change this and came up with a way to bring Apple's messaging platform to Android phones. The solution likely isn't practical for most people but it's a clever hack nonetheless: You'll need to download an OS X server and set up a Java Web Server.
The open source project by Eric Chee is called PieMessage and can be seen in action in the video above. Basically, PieMessage uses an AppleScript to read iMessages as they arrive on a Mac, after which a Java app takes those messages and forwards them to a custom app on an Android phone. You can reply to one-to-one messages from Android but currently group chats are read only. You also can't see when someone is typing or even send photos – though Chee plans to add more functionality in future updates.
Of course, your Mac will need to be on and awake if you want the hack to work.
This isn't the first time that we've seen someone try to implement iMessage for Android. However, previous attempts have relied on a third-party server to route messages, raising security concerns among users. With PieMessage users run their own server.
Chee says the system is a proof of concept and there's always the chance Apple will kill it in a future update. If you want to contribute to the project or are just curious to try it out, the OS X and an Android clients as well as all necessary scripts are available on GitHub.