Is wifi selectively deactivated in sleep mode?

[Commodore]

How exactly does (or should) wifi behave when iPad or iPhone goes into sleep mode? Does it get deactivated to save battery? I know I had to install Insomnia tweak in order to keep SSH server running. But on the other hand, it doesn't make sense that you suddenly get disconnected from SIP apps, Twitter, email, Viber, messengers, etc. just because the screen went off. Do these apps have different way around using the wifi connection also in sleep mode, or what?

 

[KevinJS]

Just taken this series of screenshots.


When I did my first scan (sorry, no screenshot) my iPhone was asleep in my pocket. It did not show up on my network. I woke it up and scanned again.





I put it back to sleep, and immediately scanned again. It still showed up on the next scan.





I waited and scanned again. This time, the IP address was still occupied, but the phone was not identified.





...so I sent it a Wake Packet.





Sent from my stock iPad 2

 

[Commodore]

So it's like some "half asleep" mode (still somehow saving battery, but accepting incoming notifications, messages, and VOIP calls)? Pure speculation on my side, though.

 

[KevinJS]

So it's like some "half asleep" mode (still somehow saving battery, but accepting incoming notifications, messages, and VOIP calls)? Pure speculation on my side, though.

That's what it looks like. Hope that was useful.

Sent from my stock iPad 2

 

[zstairlessone]

It is possible that during the time of the lease that it will show up even if not connected. You can test this by burying your iPhone about 125 feet underground and re-scanning (ok, you CAN just turn off the wifi on the phone, but where's the fun in that??).

 

[Commodore]

So far it seems it depends on app's support... I had 3CXPhone SIP client on, and it would constantly keep disconnecting (while "sleeping"), making me unreachable on that number. However, Media5-fone seems to hold its connection alive.

 

[AQ_OC]

Anytime the display is off on an iPad huge battery life is being saved unless you turn screen brightness to almost zero.

Certain activities can happen in the background and when the screen is off. For example, backup via wifi can take place when the screen is off. Music can play. Also, navigation apps operate in the background, as does music and other audio applications.

You probably need to ask a developer to find totally comprehensive info on what can operate in the background and what the real definition of "sleep" is. It is clearly not the same thing as the screen being off.