I am in a similar position.
I have an iPhone 4 bought around launch time. For month it has worked flawlessly.
About a month ago the trouble began.
I got a lot less battery life, the phone was hot even when off and mail acted weird. For example, I have 8 accounts on the phone. 1 of them is exchange, 2 Mobile me, 2 Gmail, 2 Yahoo and an AOL. My previous phones never had a problem with this, nor did this phone at first.
First mail symptom. It would jump out of the 'All Inboxes' and into the master account every few seconds. Annoying, but manageable.
Outlook email woudl show the preview but fail to download message from server. Solution was to stop mail from multitasking, and restart it. It would work for a bit.
I decided to cut my losses and I did a full restore and rebuilt my phone app by app. I did not use the back up. All was good for a week to 10 days. Then same issues. Plus now the speed and battery life.
Every app has MASSIVE delay. Like worse than my 3G on iOS4 kind of sluggishness. Typing an email is impossible. Home button is nearly unresponsive. Battery life is hours. I unplug a full charge and never even turn on the screen and it is down to 88% in 2 hours.
I did a reset all settings. Nothing worked. I did another full restore from scratch. Nothing.
I do not think it is hardware as much as some sort of conflict. I do not ever run the location aware apps in the background, but I have downloaded a few new apps lately.
My questions are has anyone else experienced similar issues? Is it possible for a bad app to cause corruption to the system? I thought Apple checked these things. I have never jail broken this phone. I am up to date on all apps and iOS.
I will do another refresh and take it to the Apple store, but I suspect they will tell me it is a conflict of some sort. I did casually ask a few weeks ago and the Genius stated some games are known to do this.
I do not want to jhave to go app by app and keep testing configurations like the old OS9 Conflict Catcher days, but I need my phone to work again.
Other useful info:
It is connected to myc ar via bluetooth, this is also super slow and laggy. I have tried airplane mode, turning off push, rebotting, resetting all, resetting network, turning off notifications, disabling email accounts, etc.
The best performance I got was yesterday. With no Bluetooth, no Exchange email, no Push, manual check of mail, and no notifications, the battery lasted 4 hours and the phone was super sluggish still.
Using Sys Info I have no out of place errant processes I can see:
User memory 60 MB
System 69
Nice 77
Inactive 223
That is typical.
CPU load, inactive about 52% when freshly rebooted. As for process, most seem 'normal' iphone iOS related. Things like Kernal_task, launchd, syslog, lockdownd, mediaserverd, locationd, fairplay.N90, SpringBoard, BTServer, notifyd, apsd, lsd, MobilePhone,iapd, securityd, MobileMail, ReportCrash.
For example, today I am at 61%, usage 56 minutes, standby 8 hours 38 minutes. Not exactly great for a phone that went 36 hours 4 weeks ago.
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Yeah, it's just irksome knowing the phone doesn't perform as well as it did before the upgrade. I can't be the only creature of habit out there and when something changes, I'm like Dustin Hoffman in Rain Man, and freaking out about it. haha I turned off push, notifications, and wifi when not using it. I had also reset my network settings, which erased all my wifi passwords. So far, the battery seems to be as it should. If I'm that OCD about it, I'll probably just restore as new to start fresh. Apparently, thats been doing the trick for most people with this problem.
Just for the hey of it. My stats are...
47% at 8:46am
Usage:5 Hours, 39 Minutes
Standby: 1 day, 1 hour.
Pretty good in my opinion, I don't see how some of the other members go days without charging their phone. I'm going to let the battery die and give it a full charge.
