Under light Notification Badge by @deckedsg.

This does NOT indicate an app is running in the background!!! It's simply a replacement for your notification badge, minus the number(s).

Instructions: Install Boover from Cydia. It's a FREE tweak by @jontelang

Go to Settings > Boover and use the following settings: Badge position: Bottom center, Pixel precision offset Y: -4.0 (tap Move up four times), Pixel precision offset X: 0.0 (leave default), Badge scale: 1.0 (leave default), Then tap "Save changes and respring", Check mark Underlight Notification Badge in Winterboard, make sure it's at the very top of the list so it overrides any other settings then respring.

NOTE: The position is set for default icon sizes, depending on the theme you use, you might have to adjust the positioning. For any questions/comments get in touch with me @deckedsg

P.S the theme used in the screenshot is iFlat 3 Evolution.