Suggestion for app to pair with Hangouts? (explanation inside)

[ManiacalMF]

I use HoverChat, which uses Chat Heads (a la Facebook Messenger) to pop-up text messages on your screen no matter what app you're using. So if you're playing a game, watching a video, or browsing the web, you can quickly reply to a text without having to exit your current app.

The only thing preventing me from using Google Hangouts as my main SMS/MMS is this kind of feature, and I do kinda want to switch to Hangouts. Is there an app out there that will pop-up a Hangouts SMS and let me reply and dismiss like in HoverChat?