The chat heads operate like Facebook's featuring an icon of the person you're messaging. You can tap the chat head and a message bubble pops up where you can text away. To close the chat head, you simply drag it to the dock where an 'x' appears.
MessageHeads brings Facebook’s Chat Head style chat bubbles to the Messages app.
● Enable globally with option to disable on lockscreen
● Mute option for conversations
● Two docking options -- Top and Side
● Two activator actions
● Hide/show conversations
● Quick Compose
● Normal and Dark Mode
● Color customization options
You can configure options from settings and the tweak even works with BiteSMS. The tweak does require iOS 7 and is available for $2.49 in the Cydia Store.