If this sounds appealing or interesting to you, you can download the client app as well as the server from the developer website: Note youll also need to, and enable some specific accessibility features that allow weMessage to run as expected. Use either, or neither, thats up to you as well.
Note this approach is different from by screen sharing, though you could certainly replicate that approach on Android too with a VNC client as well if desired, which would circumvent the need to use a third party service to relay any messages. Whether or not you trust a third party service to relay your messages is up to you, but if you absolutely must have iMessage sending capabilities on an Android phone or tablet then this may be a reasonable solution. This is achieved by running a weMessage server app on the Mac, which allows the client weMessage Android app to send and receive iMessages. The Mac is necessary because weMessage works by essentially using a Mac as a software relay point, which then passes the messages along to the Android device and accompanying Android app, and vice versa. But there is a catch you must have a Mac, along with an Android device of course. Its called WeMessage, and its a third party effort that uses an interesting workaround to gain iMessage on Android devices.
If youre an Android user and you wish you had iMessage on your device, youll be happy to hear about there is a solution that effectively brings iMessage onto an Android device.