iMessages on iOS 8 has also been updated with some new features resembling whatsapp.
iMessages on iOS8 now lets you send audio and video messages to individual or group messages. You can now add or remove people from group chat just like you do on whatsapp. Apple has also added "Do not disturb" feature through which you can turn off the notifications in the group chat.
iMessages also features location sharing service in group chat, you can control your location sharing by time and even turn off the location sharing. One of the interesting features of iMessages is that you can now respond to iMessages notifications directly from lock screen.
When you get an audio message you can just bring the phone near your ear and it will automatically play the message, similarly you can send the audio message this way. There are self-destructive messages too like Snapchat so Apple is trying to bring all the best features of different social apps in one package.