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When playing Ingress I find that both GPS and WiFi (each by themselves) provide an acceptable location accuracy. My question is what draws the most power?

I'm interested in technical information about what goes on in my phone when I use either service to find my location: how much power does the WiFi radio take compared to the GPS?

My thinking is that

  • Enabling WiFi requires powering on a chip and using an antenna that both sends and receives data. Is that correct when I'm not actually connected to any network, i.e., just using the SSIDs along with cell tower IDs to determine my location?

  • Enabling GPS requires powering on an otherwise dead chip that does expensive computations to compute the location. Is the constant GPS computations really expensive in terms of power drained?

My phone is a LG Nexus 4, if that matters.

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  • Do some benchmarks yourself. One day play with both. One day with only WiFi, and another with only GPS. See what happens. – ElefantPhace Apr 16 '13 at 7:21
  • @ElefantPhace Thanks, but I feel such benchmarks would be unreliable: I play more or less on different days, I receive different amounts of email, I use Google Maps more or less, etc. – Martin Geisler Apr 16 '13 at 7:33
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    While your WiFi AP is near you, GPS satellites are in orbit and thus the signals are very weak when it reaches your phone. GPS power consumption is extremely high compared to WiFi. Most phone lasts less than 10 hours on GPS while with WiFi they can last more than day. – roxan Apr 16 '13 at 8:24
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    Check this answer, which gives you some indicators. It contains measures from two different devices. – Izzy♦ Apr 16 '13 at 9:41
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    GPS only uses power when active. The WiFi data are calculated for data transfer. So you cannot really compare it if you don't use any data. WiFi is quite power-hungry on some devices when it's permanently checking for networks -- while it's not eating that much as long as it's connected (and does not need to scan). As the scan behaviour seems to be device dependent, you can take those values only as a "raw estimation". – Izzy♦ Apr 16 '13 at 15:23
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If you look at my previous answer to a similar question you can see that by Google's testing utilising WiFi will use more battery than using GPS. This seems broadly in line with the figures given in an answer mentioned in the comments.

However as Izzy mentions these are ballpark figures and actual consumption is dependant upon what exactly the phone is doing.

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  • Actually, looking at your previous answer it looks like WiFi in standby (as it would be if you're just leaving it on for location) uses less power than GPS. The other link also shows GPS "standby" as lower than WiFi standby. I still +1'd your post for the great references. – Tom Panning Apr 18 '13 at 20:18
  • @TomPanning You're right, I should've made it more clear, it mainly answers the title question about which out of GPS and WiFi uses more power when being utilised rather than just for location. Although since the OP is using location in conjunction with sending their location back to a server the Wifi wouldn't just be in standby, unless they're using 3G. I'm also not sure Wifi would be in standby if using it for a location since it's polling for nearby networks and can also have the habit of connecting to nearby unprotected networks. I'll try and find some more info to add to the answer. – Peanut Apr 19 '13 at 5:11
  • WiFi is propably consuming more energy when using better than 2G/Edge – Nils May 27 '13 at 15:35
  • @Peanut - If the Wi-Fi is just being used to determine location, will it use less power than a GPS? – Robert Jul 7 '16 at 17:22
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On the LG Nexus4 power consumption is very high when using 3G+ internet connections.

And as you wrote GPS is a passive method. CPU does not seem to matter much here (my own findings after a few months of usage).

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