i have rewritten this, hopefully more clearly.
battery whore, but very accurate: gps
use wireless networks: self explanitory - ONLY cell towers are used. not as accurate as gps.
use sensor aiding (actually a passive wifi locator): even if your phone's wifi is turned off, even if your gps is turned off, if you walk or drive by a starbucks, your phone still passively "picks up" wifi signals" and the wireless network towers better know your exact street address. if your gps is turned on, this helps reduce the stress and power used by the gps pulse to find you. sensor aiding will definitely save battery. sensor aiding also helps wireless networks/towers to find you more accurately. most restaurants, coffee houses, retail stores, shopping centers, etc., etc. have free wifi today.
in my opinion, sensor aiding will always help save battery by using wifi hotspots to send your EXACT street address. sensor aiding will not help on a road trip in the middle of nevada or montana. think of sensor aiding as a passive wifi locator without you turning on your wifi in a city. so, yes, sensor aiding will ALWAYS save battery.
in the middle of nowhere, gps will work better if you also have wireless networks turned on to better find you.
in a city, i would use wireless networks and sensor aiding, period. cities have plenty of network towers, so in a city, gps is not really needed.
does this better explain it? if not, turn on google maps, and walk around your block and experiment using the different settings to see what you think. just remember, gps is a battery whore!!
