This is a WhatsApp clone that I tried creating. I used Firebase to implement real time database. You can login in this using your E-mail or Google account. Features like changing your profile picture and updating your status are also implemented.
Link for APK = https://drive.google.com/file/d/1InFKbg9x3tK1sgqij2ivfi_R5Mgf0F2I/view?usp=sharing