Will constantly having Bluetooth on drain my battery too fast?

Question

I'm thinking about making an app which will require Bluetooth to be available at all times. However, if this reduces battery charge life significantly, then that's kind of a show stopper. Can anyone give me a general idea about how much drain constant Bluetooth use will put on the battery?

Answer 1

Constant use of Bluetooth will put quite a significant drain on the battery, even having it on is known to drain the battery.

Answer 2

It really depends on what you are using Bluetooth for. I have a Bluetooth watch (MBW-150) that I sync with my phone using OpenWatch and it affects my battery life minimally. All it does is sync the phone's time with my watch, vibrates on certain notifications/calls, and gives me control of my music player (play/stop/next/prev/volume). So I essentially have Bluetooth turned on all the time and haven't really seen a battery problem because of it.

Answer 3

What drains... my special. Here some data samples, based on a Motorola Droid:

+--------------------+----------+
| Mode               | Energy   |
+--------------------+----------+
| Bluetooth receive  | 751 mW   |
| Bluetooth send     | 487 mW   |
| Bluetooth standby  |   2,8 mW |
+--------------------+----------+

So if you use BT quite regularly (e.g. to be able to immediately pick up a call with your headset), having it in standby doesn't hurt that much (Compare: 2G StandBy 11,6 mW, 3G StandBy 18,3 mW, Wifi StandBy 7,8 mW -- and, often mistaken: GPS StandBy 0,4 mW).

But if, on the other hand, you use BT once a week (or even less) -- heck, you can manually enable it then, there are enough "toggle switches" and widgets available.

Answer 4

I have a Samsung Galaxy S (Vibrant):

• With Bluetooth & Sync turned on, but the Bluetooth not connected, I better have > 45% battery before I go to bed or else my phone will be dead by morning.

• With Bluetooth & Sync turned off, I only use 1-2% battery overnight.

How much of that is Bluetooth and how much is Sync, I don't know. But the combination sure kicks the crap outta my phone.