@chriskerins wrote:
I have the GPS on for runs, but turned off the auto-start feature. But if I understand it correctly, the GPS only turns on when you begin the exercise correct? The GPS is not actually active all the time? If not, can you completely turn off GPS until you want it?
That's the way I understand it, it'd be nice if Fitbit would detail their algorithmic method here.
Regardless, if you have GPS on, and "auto start" for something like walking set to "10 minutes", I'm pretty sure that it'll auto-start the GPS, once it reaches the 10 minute threshold, and keep it running, until it determines that you've "stopped" that activity.
So, say you're walking 12 minutes between buildings, for a meeting, you might get 12-20-30 minutes (this is the part you'd have to experiment to see) of GPS use, which is really battery-intensive.
In this example, even if they only ran it for 20 minutes (of the 12 minute walk that auto-started), it'd be logging an additional 480 seconds, or 1080, say if it ran to 30 minutes (again, depending on their algorithm). That's a LOT of power, to get the GPS coordinates every second, store the value, and do calculations for multiple displays, it's not surprising that it really drains in this mode.
I have my GPS setting as "off", and then if I decide I want to track a particular activity, I can manually start it, AND enable the GPS via the on-screen "gear icon", for JUST that singular activity.
There are pluses and minuses to both methods (auto vs manual start), you just have to decide what's the right balance for you.
I admit, I get really annoyed when going out for a walk (recovery, in-between fast cycling days), and it's 25F, and I have to take off my gloves and try to roll up my layers, in order to start the watch, say if I DO want to use GPS on occasion.
I'm really hoping Fitbit adds an "interval" setting, like many of the other sports watches out there, a 15second or 60s GPS track is still pretty good, for most stuff, unless you want to know *exactly* how fast you were going, all the time, for an activity.
This would make the "auto start with GPS" more usable, for me, as it'd drain a whole lot more slowly, and I don't really care if I only get 1-4 GPS points/minute, when I'm walking 2-4mph.
