3 ms·

How does this not drain the iPhone battery?

lstamour 13y ago
Bluetooth Low Energy. Unlike old bluetooth, this new service shuts down all the time to save power. In fact, apple recommends geofencing any bluetooth beacons you know will stay put, so it only starts scanning for nearby devices over bluetooth once you're within a certain radius. In this case, the app only looks for devices when you launch the app, though if you were willing to put up with a delay, you could do so on-knock. Haven't looked at the app yet. One more alternative: it could send the message and have your mac constantly looking for messages when locked. Third alternative, it pairs in the background and only once iOS notices the new device does it start actively opening communication channels. Apparently connect times are a few ms? http://www.connectblue.com/technologies/bluetooth-low-energy-technology/ http://www.connectblue.com/technologies/bluetooth-low-energy...
- cloudwalking 13y ago
  But the app has to be running in memory AND watching the accelerator AT ALL TIMES. How does that not drain the phone battery?
runjake 13y ago
> How does this not drain the iPhone battery? This is answered right on the linked webpage: Bluetooth Low Energy.
- cloudwalking 13y ago
  But the app has to be running in memory AND watching the accelerator AT ALL TIMES.
marcelftw 13y ago
The iPhone 5S M7 coprocessor can be used all the time in background without draining the battery. [quote] The new M7 coprocessor is like a sidekick to the A7 chip. It’s designed specifically to measure motion data from the accelerometer, gyroscope, and compass — a task that would normally fall to the A7 chip. But M7 is much more efficient at it. Now fitness apps that track physical activity can access that data from the M7 coprocessor without constantly engaging the A7 chip. So they require less battery power. M7 knows when you’re walking, running, or even driving. For example, Maps switches from driving to walking turn-by-turn navigation if, say, you park and continue on foot. And if your phone hasn’t moved for a while, like when you’re asleep, M7 reduces network pinging to spare your battery. [/quote]
- cloudwalking 13y ago
  But this app works with iPhone 4S and 5 too. Those devices don't have an M7.

Bluetooth Low Energy. Unlike old bluetooth, this new service shuts down all the time to save power. In fact, apple recommends geofencing any bluetooth beacons you know will stay put, so it only starts scanning for nearby devices over bluetooth once you're within a certain radius. In this case, the app only looks for devices when you launch the app, though if you were willing to put up with a delay, you could do so on-knock. Haven't looked at the app yet. One more alternative: it could send the message and have your mac constantly looking for messages when locked. Third alternative, it pairs in the background and only once iOS notices the new device does it start actively opening communication channels. Apparently connect times are a few ms? http://www.connectblue.com/technologies/bluetooth-low-energy-technology/ http://www.connectblue.com/technologies/bluetooth-low-energy...

cloudwalking 13y ago
But the app has to be running in memory AND watching the accelerator AT ALL TIMES. How does that not drain the phone battery?

runjake 13y ago

> How does this not drain the iPhone battery? This is answered right on the linked webpage: Bluetooth Low Energy.

cloudwalking 13y ago
But the app has to be running in memory AND watching the accelerator AT ALL TIMES.

marcelftw 13y ago

The iPhone 5S M7 coprocessor can be used all the time in background without draining the battery. [quote] The new M7 coprocessor is like a sidekick to the A7 chip. It’s designed specifically to measure motion data from the accelerometer, gyroscope, and compass — a task that would normally fall to the A7 chip. But M7 is much more efficient at it. Now fitness apps that track physical activity can access that data from the M7 coprocessor without constantly engaging the A7 chip. So they require less battery power. M7 knows when you’re walking, running, or even driving. For example, Maps switches from driving to walking turn-by-turn navigation if, say, you park and continue on foot. And if your phone hasn’t moved for a while, like when you’re asleep, M7 reduces network pinging to spare your battery. [/quote]

cloudwalking 13y ago
But this app works with iPhone 4S and 5 too. Those devices don't have an M7.