It's true that iMessage is only available on Apple devices, but there is a way to use it on Android phones. Third-party apps like BlueBubbles allow users to send and receive iMessages on their Android device. You can also send iMessages from an iPhone to an Android using SMS, which is the formal name for text messages. Android phones can receive SMS text messages from any other phone or device.
Although Apple has excluded non-Apple devices from the blue bubble club, there are ways to run iMessage on machines running operating systems such as Android, Windows and Linux. BlueBubbles is one of the applications that can be used to send and receive messages in iMessage using a non-Apple device. It can be used on an Android device or on any web browser, regardless of the operating system, using a web client. Developers are also creating dedicated desktop versions for Windows and Linux. If you have the right software, the right type of computer and some technical knowledge, you can set up iMessage for your Android phone.
BlueBubbles shares an extensive setup guide on its website with step-by-step instructions on how to use iMessage chats on Android, Windows or Linux. Apple isn't likely to release iMessage for Android anytime soon, but there are other applications like AirMessage and WeMessage that can help. WeMessage works by sending your texts to its server which then sends them to iMessage. This means that all your texts are sent to WeMessage and then to iMessage to be sent from macOS, iOS and Android devices, while still using Apple encryption. The desktop app's settings are the same as those on Android, but you probably can't scan a QR code with your PC. To test if you can send iMessage text messages from Android, send a text message to an iPhone; if the text bubbles are blue, it works! Unfortunately, it's not possible to download iMessage for Android through the Google Play Store or upload it directly to your device without Apple's help.