Looks like a hardware issue - have you upgraded recently to a new operating system ? Could also be an issue with your router - power cycle it and test some other devices against it. Every fewmonths my router (Netgear) decided it will give out IP addresses and then cancel the lease ..... after a power cycle it's fine.

turn off push and notification services in settings and reboot - see how it goes for a day and then turn back on.

Unfortunately - the hardware is slow in modern terms - he needs an upgrade. Eventually, running windows 7 or macos on a zx81 will be slow :)

the switch for facetime is in Settings/Phone if you cant find it

A tip for iPhone 4 owners - if you wonder what's chewing up few meg of cellular data/day in stdby even if you have push/notifications set to off, it's facetime causing a tcp connection to stay open in standby to the apple push servers. It checks in every 5 minutes over cellular and in doing this reduces stanby by about 1/3rd. When you turn the phone on it spins up the wifi chip but in standby, it resorts back to the cellular data. I disabled facetime as I dont use it, rebooted and now, no more phantom usage. Personal thanks to my OCD and netstat for finding this :)

-scott.

Just wanted to add my Christmas whishes to the devteam, who have kept us all in JB's for the last umpteen years and everyone else on the forum ! My brother is coming through today with my original 1st gen iPhone that still has the wifi issues (only works after 10 mins in the freezer). Ah - the "old" days. When I have a gripe with my new V4 or indeed my 3G I just think back to those days of feeling good if I answered a call without it crashing :)
I will finish on a joke from my wife
Q: How do you know someone has an iPhone
A: They will tell you ....

-scott.

:) Here it comes - once the devteam have had their festivities of course

this should be the pin you had on the sim perhaps in an older phone. Try putting
the sim in another phone and see what it does. If it still asks for the 4 digits then
key in what you set or talk to the person who you got the sim/phone from.

Please help :)
Since 3.1.2 came out I have been keen to update but last night I had a huge accident.
After reading the instructions with care and following each step it appears I have successfully
upgraded, unlocked and Jailbroken my phone. I dont know what to do, I was looking forward
to a week of hell trying to unbrick and downgrade; then a 5 month wait for new tools posting
daily complaints on this blog. Damn, if only I had let my 75 year old next door neighbor do it for me.
My life is now in ruins as I will have to spend the weekend with my wife and kids. Please help

PS-As is usual devteam ... great job on a slick tool .... to all the moaners .... this is why it takes them time
to publish their material .... so it's usually flawless (if you read the instructions and take care). I've
used these tools for years and the only time it went wrong for me ..... I didn't read the whole set of
instructions. iPhone+Jailbraking+Haste=Disaster

Things I note in 3.1.2 on my 3G (coming from 3.0)
1) GUI faster - less laggy (got rid of the -g flag :)
2) 2G calls dont tear through my battery as much (radio power management?)
3) Push seems less aggressive in battery use (initial view this may change)
4) No 10 second delay after bootup now
5) Carrier logo missing (but I know who my carrier is)
6) Icon management in itunes
7) Web browsing seems faster and my phone is for sure less hot when streaming video
8) GPS use still hemorrhages through the battery like an aluminium smelter set at 10
9) Wifi now picking up my marginal signal from my living room router in my office 5 bars .....

To me it feels like a 2.2.1 type of upgrade (more benefit than harm).

Strange as it may sound - (google for 2.2.1 killed my wifi and you will see some of my posts about the issue with some older wifi chips that fritz when a newer firmware is loaded (that possibly unthrottles them). Put your phone in a freezerbag and place in your freezer for 2-3 minutes - now try the wifi. I first read this 9 months ago and thought it was madness - as the phone was not under warranty anymore I gave it a try - wifi came back for a couple of hours - it's a heat issue on a lot of older phones.
Your other option is borrow an official carrier sim from a friend and use their cellular data signal to download ultrasnow.