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>This is why in urban areas it usually makes more sense to use cell network to save battery Hmm. Rhen why does Apple recommend using WiFi for power saving? “W

>This is why in urban areas it usually makes more sense to use cell network to save battery Hmm. Rhen why does Apple recommend using WiFi for power saving? “When you use your device to access data, a Wi‑Fi connection uses less power than a cellular network” https://www.apple.com/batteries/maximizing-performance/ https://www.apple.com/batteries/maximizing-performance/

tidepod12 6y ago
There's a lot of confounding factors, but in general: Cell network uses very little power when idle, but a lot when transmitting. Wifi on the other hand uses a medium amount of power when idle, and a medium amount when transmitting. (this is really generalized and there have been a lot of recent advancements to optimize power usage of both). This is why general guidance for years was to use wifi when you are actually using your phone for browsing the internet, taking advantage of wifi's lower power efficiency when in use, but to turn off wifi when your phone is just in your pocket/idle to take advantage of cell network's better idle power efficiency. However, the above is really only true for urban/suburban areas where you have good signal. If you are in an area with poor signal, your phone will use a lot of battery power via the cell network even when "idle" (because in reality even though your phone is "idle", the cell radio isn't actually idle, it's constantly struggling in the background to maintain the connection through the poor signal).
- joecool1029 6y ago
  Just adding onto your comment, Apple probably recommends use of wifi because: 1. They collect AP's for their mapping/location crap. 2. The wifi chipsets they use are basically their own self-contained computers that can manage scanning at low-power without taxing the CPU. 3. At least for new HW, some of the 5G-NR stuff really isn't well optimized yet, not as bad as LTE originally was... but it's entirely possible the new modems for now are a little power hungry. Turning on wifi makes the cell chipset track less carriers, typically it'll just hug to one low-band carrier for status/push messages instead of as many as 5 or 6 carriers. EDIT: Phones usually only transmit on one channel while receiving anywhere from 1-7 different channels at once, only the recent flagships transmit on 2 or 3 right now.
  - kortilla 6y ago
    > Apple probably recommends use of wifi because: 1. They collect AP's for their mapping/location crap. Nope. And the reason this is obvious is because turning off WiFi via the control center doesn’t actually turn off WiFi so collecting SSIDs wouldn’t be a problem either way.

tidepod12 6y ago

There's a lot of confounding factors, but in general: Cell network uses very little power when idle, but a lot when transmitting. Wifi on the other hand uses a medium amount of power when idle, and a medium amount when transmitting. (this is really generalized and there have been a lot of recent advancements to optimize power usage of both). This is why general guidance for years was to use wifi when you are actually using your phone for browsing the internet, taking advantage of wifi's lower power efficiency when in use, but to turn off wifi when your phone is just in your pocket/idle to take advantage of cell network's better idle power efficiency. However, the above is really only true for urban/suburban areas where you have good signal. If you are in an area with poor signal, your phone will use a lot of battery power via the cell network even when "idle" (because in reality even though your phone is "idle", the cell radio isn't actually idle, it's constantly struggling in the background to maintain the connection through the poor signal).

joecool1029 6y ago
Just adding onto your comment, Apple probably recommends use of wifi because: 1. They collect AP's for their mapping/location crap. 2. The wifi chipsets they use are basically their own self-contained computers that can manage scanning at low-power without taxing the CPU. 3. At least for new HW, some of the 5G-NR stuff really isn't well optimized yet, not as bad as LTE originally was... but it's entirely possible the new modems for now are a little power hungry. Turning on wifi makes the cell chipset track less carriers, typically it'll just hug to one low-band carrier for status/push messages instead of as many as 5 or 6 carriers. EDIT: Phones usually only transmit on one channel while receiving anywhere from 1-7 different channels at once, only the recent flagships transmit on 2 or 3 right now.
- kortilla 6y ago
  > Apple probably recommends use of wifi because: 1. They collect AP's for their mapping/location crap. Nope. And the reason this is obvious is because turning off WiFi via the control center doesn’t actually turn off WiFi so collecting SSIDs wouldn’t be a problem either way.