DirectChat allows you to create ChatHeads for any app or messenger. It manages all your conversation in one place to help you to have a convenient conversation without interrupting your current task such that you can read and reply to all messages without ever coming online. It comes with 16 messengers support by default. It is also suitable if you want all your notifications to appear in ChatHeads. You can also customize the chat appearance to suit your needs with different colors and transparency.

Features
ChatHead Support for all apps
Privacy Mode - Read and reply to all your messages without coming online!
MultiWindow/MultiTasking - Chat over the top of any window!
Clean Arrangement - New ChatHeads will appear on top of each other in the form of stack and won't clutter your window.
DND Mode - Pause the ChatHead Service temporary
Blacklist Apps - Disable ChatHeads to appear on certain apps
Blocked Users - Disable ChatHeads to appear from certain users.

Pro Features
No Ads
Chat Appearence and Themes
Bubble Transparency
Chat Window Transparency
Enable as many custom apps as you want..
Many Predefined themes for various apps.

Default Supported Messengers
WhatsApp
Kik
Hangout
Telegram
Allo
Textra
Skype
Facebook Messenger
Threema
Line
Disa
Plus
Slack
GroupMe
Messenger Lite (for Android N+)
Viber

You can add your own by going to app settings and enable the apps for which you want to display chatheads.

*Reply functionality will only be visible in apps that support it.