iOS 6 (and earlier) will turn off WiFi when the sceren locks if all the following are true:
- There is a cellular data connection availalble and cellular data is turned on.
- The iOS device is not set up to sync wireless to iTunes or is associated with a WiFi network other than the one it was connected to when wireless syncing was set up (i.e. not at home).
- An app (Apple's or 3rd party) is not requesting Wake On Wireless (WoW) functionality. Some apps (primarily VOIP) force the device to stay connected to Wireless. Apple also sometimes forces the device to stay connected to wireless if the cellular signal is too weak (see #1) and it will switch to using Wifi for push notifications.
If any of the above is not true, WiFi will remain active when the screen locks. Supposedly the device is also supposed to stay connected if charging or plugged in, but I've found that isn't always the case.
Note, I've found a bug in IOS 6 which sometimes causes the WiFi to drop regardless if the screen is locked or not. This is because Apple periodically polls http://www.apple.com/library/test/success.html while connected to WiFi and if it fails for some reason, it simply drops the WiFi connection. The only way I've found to get it back is to manually reconnect in the Settings or to open one of Apple's Apps (Mail, Safari, etc).
I tend to agree . See my response to the other thread below. Us iPod users can't even switch to the mobile network to bypass the problem! Certainly if the wifi was being woken by my work router under IOS 5 it is not any longer.
Well here is my experience. I had no problem with my iPod Touch 4 running IOS 4 or 5. And I still have no problem with my home router a BT HomeHub 3, I get push notifications etc.
What has changed is the behaviour at my work which uses a Cisco login system set to a 12 hour timeout. Now under IOs 6 the wifi is dropped on sleep when the pod is not plugged in and doesn't receive push notifications. This is new behaviour under IOS 6. Then on wake I have to log back in. If I keep it attached to the charger the wifi is maintained when sleeping.
This suggests to me:
* This is a change with IOS 6.
* It is not simply an attempt to save battery life by turning off wifi; it works with my home router fine.
* It is dependent on router type or the form of communication on sleep which has changed and that may be something to do with changes made to fix wifi battery drainage issues.
This is NEW iOS 6 behavior, it has nothing to do with the router and it's stupid.
I need to turn off cellular at work, since there is no reception in my building. In previous versions of the phone I was able to receive push notifications (including e-mail) and iMessages. I have tested this both at home and at work, and now with the phone asleep nothing comes through until I wake the device.
What's worse, is that if I leave the cellular on and it's searching for signal all day (thus draining the battery even more!) push notifications will work over wifi. I know it's not over cellular because there is absolutely not service (lead lined walls).
Obviously this is a software setting, so I'm not buying the excuse from apple that it can't be changed. Just give us the option of having persistent wifi or longer battery life. Or I will be considering the option of using Android.
I think that we go t to a point where understanding what is going on is very clear.
Apple knows about the real weak point, the battery life, instead to release a better battery (maybe more expensive) "plays" with the excuse of routers, g3 and whatever they want...
The thing is that there are 2 kind of users. A.old apple user, which would buy job's excrements thinking that is nutella
B. Demanding users
I defo belong to the B options
good luck all !!!
Yet what else explains the fact that the new behaviour in IOS6 only seems to manifest itself (in my and others' cases at least) when running on battery power. When it's plugged in to power, and sleeping, wifi remains active (or at least able to be pushed to by the router).
Morac's points are interesting though it doesn't quite explain the difference in a work situation between being connected to power and not.
Confirmed on iPhone 4 with ios 6.
iOS must have an option to keep wifi on during sleep. This will help:
1. Save data usage when you're connected to home/office wifi (unless of course Apple is doing this to make more money with the telephone companies who charge an arm and leg for data usage).
2. Save battery drain when data connection is not good and wifi is strong
Android has this useful option, why not iOS?
I just wanted to chime in as I was having the exact same problems described in this thread. I have a brand new iPad 4 (wifi only) that is literally 2 days old, came preinstalled with iOS 6.0.1 out of the box. I confirmed via ping that wifi always shut off shortly after locking. Once it was locked, the iPad would never get any notifications (e.g. mail, FaceTime, iMessages, etc.) until I unlocked it and it reconnected to wifi.
What fixed this issue for me was to do a restore (not a restore from backup but restore to factory state) from iTunes.
1) I installed the latest version of iTunes (11.x)
2) I chose the option under the iPad section within iTunes to restore my iPad (do not restore from backup!). This caused iTunes to first download iOS 6.0.1 to my PC, then it installed iOS 6.0.1 onto my iPad. This put the iPad into factory state.
BINGO! Now I am receiving all notifications again as in 5.1.1.
I know what I'm doing around computers for the most part as software engineering is my profession. I tried everything mentioned in this thread including all of the network/router tweaks, and seriously nothing worked until I did the restore from iTunes. I tried this as a suggestion from an apple tech over the phone. I was skeptical because my brand new iPad was already on the latest firmware. Obviously because restoring from iTunes worked for me it leads me to believe that there are slight variations in the iOS version, or some packages get corrupted for whatever reason.
I hope this helps some of you. As a side note, my wife has an iPad 3 running iOS 6.0 that was updated over the air and has never had these notification issues - so go figure :-)
Yes that is correct. After notifications started working, pings still failed when the iPad was locked. When a notification came in it was like the iPad "woke up" to receive the notification. As soon as that happened I could ping it again. So even though it appeared unreachable on the network, notifications are able to wake the iPad appropriately.
I've had an iPhone 3GS long ago. I used it for a few days and reverted back to my old phone because I didn't like it.
Sick of my Android phone and just bought an iPhone 5.
Here are my findings.
iPhone 3GS after the screen shuts off (haven't timed it). Results - The TRANSIT signal turns off. RECEIVE signal remains active. Probably lowers its antenna power as well since the rate drops very low.
iPhone 5 on iOS 6 - BOTH Transit and Receive shut off.
My Wifi Setup... No Security.
This is an iOS 6 problem (or "feature") it seems.
Everyone trying to restore your phones... Stop. You are embarssing yourselves. There obviously are lots of anti-Apple people here trolling you. I would like to see a fix as well.
How do you test for TRANSIT vs. RECEIVE?
Also I'm definitely not anti apple, I own multiple apple products. I simply commented on what worked for me. Trying to restore the iOS Firmware image is not silly or embarrassing. Like I said I was very skeptical to try it because I was already on the latest firmware for the iPad (6.0.1), however either something must have been corrupt in my pre-installed image or the firmware I restored via iTunes download (not restore from backup) was slightly different - but trust me that did fix my problem. I haven't done any scientific testing of the wifi signal other than network pings to verify when it was reachable/unreachable, and of course testing to make sure notifications came through.
I have also noticed that notifications are hit and miss when I have a poor wifi connection (1 or 2 bars). Note this is just based on my experiences - I haven't tested this theory fully. For example on the same network I would consistently receive notifications when my signal was strong, however when I went to an area where the signal was weak I would consistently not receive notifications.