iOS 4 is laggy for most people who have the iPhone 3G. I have since downgraded back to 3.1.3. It’s much more usable even without all the new features. So if you upgraded to iOS 4, I highly recommend you downgrade.
Please follow the instructions here:
http://www.iphonehacks.com/2010/07/how-to-downgrade-iphone-3g-from-ios-4-to-iphone-os-3-1-3.html
To disable data on iOS 4, go into Settings -> General -> Network and turn off the Cellular Data option.
*Works on all iPhone firmwares up to 3.0 and most cellular carriers*
* Personally tested on my iPhone 2G/3G 3.1.2 on Rogers *
If you have an iPhone but didn’t get a data plan be in for a shock after you see your bill. When out of range of a Wi-Fi access point, the iPhone will automatically connect via EDGE/3G periodically incurring expensive charges. Usually 5 cents per kilobyte, 1MB is $50!
Here is how you disable it.
1. Launch Safari on your iPhone
2. Go to iphonenodata.com
3. Tap the “Disable EDGE/3G” button
4. Tap “Install”
5. Tap “Install Now” to confirm
That’s it!
Go to “Settings – General – Usage” to check if you’re using anymore data. The counter shouldn’t go up from on. As you can see, my phone never ever used any data.
If you try to browse a web page, this is what you see. Data is blocked
.
Lots of people have reported iPhones that drain very quickly since upgrading to a new firmware. It has nothing to do with this profile since I have iPhones that don’t even have Edge/3G disabled through profiles and it exhibits this issue. Here’s what fixed it for me. Be sure to setup as new iPhone and also turn off notification as per the images below. My battery doesn’t drain as quickly as it did before. If you googled this issue, you’ll see that this is an ongoing problem with Apple. Hopefully one day a new firmware will fix it for good.
This is from http://blog.iphone-dev.org/
Unusual battery depletion is almost always caused by people choosing to “Restore from backup” instead of “Setup as new iPhone” when iTunes asks you. This isn’t caused by either the jailbreak or the unlock, but it’s a common 3.0 snafu. The fix is to just re-run the official 3.0 restore and choose “Setup as new” this time. Your music and apps and all that will still be synced, but you’ll get rid of any conflicting wifi, bluetooth, or carrier settings.
One of my iPhone’s batteries drained extremely fast. It’s on Firmware 3.1.0 and 3G was enabled (I have a data plan for this phone). I found that if you disable notifications it was back to normal.
Learn about the download options you have when you purchase a TV season, Season Pass, movie bundle, music box set, or an individual movie or TV episode using iTunes 11 or iOS 6 or later.
Learn how to find movies and TV shows on the iTunes Store that have closed captioning, and find out how to enable captions on Apple products.
This document describes the security content of iOS 6.1.
For the protection of our customers, Apple does not disclose, discuss, or confirm security issues until a full investigation has occurred and any necessary patches or releases are available. To learn more about Apple Product Security, see the Apple Product Security website.
For information about the Apple Product Security PGP Key, see How to use the Apple Product Security PGP Key.
Where possible, CVE IDs are used to reference the vulnerabilities for further information.
To learn about other Security Updates, see Apple Security Updates.
iOS can use Location Services to determine your current position.
When you are on a call using the speaker option, you may not hear VoiceOver audio as loud as expected.