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No5tromo

macrumors 6502
Original poster
Feb 17, 2012
388
969
Can somebody please explain to me how wifi works on the iPhone? I've seen people saying SO many different things and I'm really confused.

When the iPhone is locked and I try to unlock it, I see the 3G icon instead of the wifi icon and after a split second the wifi icon will appear again, this doesn't usually happens when iPhone is plugged in and charging.

Some people say that this is normal since the iPhone turns off wifi while sleeping to preserve battery (so how come iPod touch gets push notifications in sleep mode and its battery life is great?). Alright, so what I did to check this non-sense argument was to turn off cellular data, then I sent me a push notification while iPhone was "sleeping" and like I expected I received it right away, which means that wifi works in sleep mode just fine despite the fact the appearing and dissapearing behavior of the wifi icon remained the same when I unlocled the iphone (which makes the fact that this won't happen while the phone is charging very weird).

Even though everything indicates so far that wifi keeps working in sleep mode, I noticed that on my phone (while in sleep mode) it will eventually completely lose the wifi connection after a random perdiod of time which could be a few seconds or up to a few hours which means that it will either swap to cellurar data if celluar data is turned on, or I will have to deal with the fact that I will be missing important push notifications (if you are to tell me that I'm not supposed to turn off celurar data to get push notifications while in sleep mode please show official proof from Apple that this is in fact true). Finally when I wake up my phone from sleep mode it takes a few seconds until it eventually automatically re-connects to wifi.

So my question is what on earth is going on with wifi signal in sleep mode? I would really appreciate if someone with real knowledge on the matter gave me an answer.
 
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Applejuiced

macrumors Westmere
Apr 16, 2008
40,672
6,533
At the iPhone hacks section.
That's how wifi functioned ever since the original iphone.
It disconnects to preserve battery while the phone is in sleep mode then reconnects a few seconds later when screen turns on. Stays connected when charging.
Push notifications will come through using carrier data. Those are very small kb's worth of data so if you worry about your data plan dont. If its just push and imessages that will come in when the phone is in sleep mode and will use very minimal data amounts.
 

No5tromo

macrumors 6502
Original poster
Feb 17, 2012
388
969
That's how wifi functioned ever since the original iphone.
It disconnects to preserve battery while the phone is in sleep mode then reconnects a few seconds later when screen turns on. Stays connected when charging.
Push notifications will come through using carrier data. Those are very small kb's worth of data so if you worry about your data plan dont. If its just push and imessages that will come in when the phone is in sleep mode and will use very minimal data amounts.

but how do you explain that I get push notifications in sleep mode even when I turn cellular data off?
 

No5tromo

macrumors 6502
Original poster
Feb 17, 2012
388
969
Good question.
Maybe it pings wifi every so often and checks periodically.

Yea, that's what I'm suspecting...
unfortunatelly though my iPhone loses connection over wifi on lock screen completely after some time, it could take hours but usually it's after a few minutes after which I won't receive push notifications unless cellular data is on
 
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