foothillfanatic said:
I recently purchased a Logitech solar powered keyboard/case for my iPad2. I noticed that after leaving it in the closed case for a few hours that the iPad battery was soon depleted. There were no instructions stating that the bluetooth needed to be turned off when not in use. My question is, does bluetooth use the iPad battery when left on?
Bluetooth uses an antenna to send and receive signals. Thus, it uses energy. I have BT on all the time for my phone, but it goes to sleep when one of its pairing devices is not near by. I have my phone paired to my car and to a speaker. Heck, it is enabled right now on my iPad. But the BT icon in the upper right corner of the screen is greeted out, so BT is not on. But since nothing is in range it turns itself off. If you leave two devices close then BT stays on if they can "talk" to each other.....the battery drain can be very rapid then. In my car, my phone will get warm (indicating battery drain) when streaming music, so I keep it on the charger. I haven't noticed this with my keyboard, but they are very close together and there is much less info to transfer. So, yes, BT can drain the battery under certain circumstances, but it is also smart enough to go to sleep the the pairing cannot be maintained....and you typically have to wake it up to re-establish a connection. But that seems to depend...my phone always wakes up when I get in my car, but my keyboard and speakers don't. This might be device dependent, somehow.
