This app was mentioned in 16 comments, with an average of 3.75 upvotes
There's also Flychat: https://play.google.com/store/apps/details?id=com.flyperinc.flychat
I go back and forth between using it. Sometimes it's convenient, but other times it's just a bit annoying and gets in the way of whatever I'm trying to do at the moment.
There's an app flychat, you can add your own messenger apps and it'll display a popup for that app whenever you get message. I find it really helpful.
https://play.google.com/store/apps/details?id=com.flyperinc.flychat
I found this app a while back that essentially added chat heads for a bunch of messaging apps, so I guess it's possible but the app will have to support it.
Flychat 4/5 stars (1,754 ratings) Flychat offers a revolutionary way to read messages of your favourite messengers. It overlays every other app and you ... Free https://play.google.com/store/apps/details?id=com.flyperinc.flychat&hl=en&referrer=utm_source%3Dgoogle%26utm_medium%3Dorganic%26utm_term%3Dflychat+app&pcampaignid=APPU_1_gGhxWObhJsXaU7f6utgF
Made by the same dev who created Flyperlink, this app brings FB Messenger's chat head function to all your other chatting apps.
Right now it supports a wide variety of apps like Telegram, Whatsapp, Messenger, but no Allo yet.
The only thing that bugs me about the app is when you reply a message, they aren't marked as read so notifications will still appear. But the dev has a roundabout solution where you can clear notifications if the Flychats appear.
Edit: The XDA thread is here
flychat, maybe?
I use Flychat
Never have to unlock my phone to reply to messages
https://play.google.com/store/apps/details?id=com.flyperinc.flychat
Well damn, this is pretty cool
<strong>Flychat</strong> - Free with IAP - Rating: 87/100 - Search for 'Telegram' on the <strong>Play Store</strong>. ------. ^Source ^Code ^| ^Feedback/Bug ^report.