How large is the battery emissions while running an iOS Bluetooth Low Energy app in the background

Question

I need want to know how large is the battery emissions while running an iOS App in the background that is scanning for iBeacons in the near.

Does it cost much battery?

Answer 1

Not much.

When no app is ranging for iBeacons in the foreground, iOS only does a Low Energy Bluetooth scan to look for iBeacons for a few seconds out of every several minutes. See: http://developer.radiusnetworks.com/2013/11/13/ibeacon-monitoring-in-the-background-and-foreground.html.

I do not know the exact numbers in terms of mAh used, but I would be surprised if it had any significant drain on battery at all. It is much less than the display, GPS, WiFi, Cell Radio, etc.