Where does this floating icon on my homescreen come from?

A

AC Question

A little while ago a floating icon suddenly appeared on the right side of my home screen. It looked like a small blue bird, and it was animated. Pressing the icon didn't bring up any context menu (ie delete it), I could only move it around. Upon releasing the icon, it tried to open up a suspicious web page, so I rebooted the phone. Icon was gone for a day or so, and then it suddenly appeared again, shortly after I enabled my wifi connection.

Looking through my apps, I didn't see anything I wouldn't recognize. One semi-suspicious app I recently installed was an Emoji Keyboard, so I deleted it. No change. Browsing through the phone, I found the offending icon's images in android\data\..\cache folder along with some files, so I deleted them. No change. The problem was back within a couple of days, this time a different icon, but the same behavior. I looked again at the running processes and found a "FloatingService" active with a timer corresponding to how long the offending icon has been floating on the screen. Stopping the service killed the icon, but just temporarily. I decided to do a factory reset, and for a few days I thought I won the battle. Nope. Today another icon popped up in the same spot - a cute little big-headed bug-eyed guy. Since the factory reset I only installed three apps - SwiftKey Keyboard, Strava running&cycling, and Wifi Analyzer, updated preinstalled apps and downloaded a google map for offline use.

I took snapshots of the latest incarnation of this floating icon and will try to post them. If anyone has any insight into this problem, please let me know. BLU Studio C, Android 5.0, Kernel 3.10.54.