If you have iOS4 jailbroken iPhone irrespective of any baseband (including 05.13.04, 05.12.01), to have a carrier unlock, you can use ultrasn0w 0.93 available in cydia. ultrasn0w is available in cydia, so you need to jailbreak your iPhone before you can unlock it. here is step by step guide to unlock iOS4.

Step 1. Start Cydia on your iPhone and tap on Manage
Step 2. Tap on Sources
Step 3. Tap on Edit and then tap on Add
Step 4. You’ll see an input box, enter http://repo666.ultrasn0w.com url and touch Add Source
Step 5. Cydia will now update source list, Now touch Search
Step 6. Search for ultrasn0w 0.93, you’ll see ultrasn0w 0.93 listed down in the result.
Step 7. Install it and restart iPhone
Step 8. And here you have a fully unlocked iPhone. Enjoy !!!

If you have tethered jailbreak then rebooting iPhone may stuck iPhone on sn0w screen, to overcome this issue follow last section of this post.

Dev team has released PwnageTool 4.0 for iPhone 3GS on Mac. You must know few points before you start upgrading your iPhone 3GS

• You must own a mac
• Not have jailbroken previously with Spirit
• Have a hacktivated iPhone running iPhone OS 3.
• You have not upgraded to iOS 4

If you are running jailbroken iPhone OS 3.0, 3.1.1 or 3.1.2. You can upgrade to iOS 4 by following the instructions given here .
After you upgrade, let us know your iOS 4 experience.

The redsn0w beta has been updated for 4.0GM on iPhone 3G and iPod touch 2G (non-MC version). Multitasking and homescreen wallpaper are turned on by default (Apple doesn’t normally allow this on these 2 devices). You can deselect these features if you choose.

A version for Windows is now provided.

Just like our other betas, this one intentionally doesn’t “hacktivate” the iPhone. Please wait for Apple’s public release of 4.0 for that part of it.

YOU SHOULD STAY CLEAR OF THIS BETA SOFTWARE IF YOU RELY ON A CARRIER UNLOCK. That’s because the beta redsn0w works only if your device has already been upgraded to the stock 4.0beta1/beta4/GM IPSW from Apple, which contains a baseband update. If you installed that IPSW, you’ve already lost the carrier unlock until the next planned release of ultrasn0w and blacksn0w.
To read more click here

In this tutorial you’ll jailbreak/unlock firmware 3.1.2 for iPhone 3GS using BlackRa1n. Before continuing, please make sure that you are on 3.1.2 firmware and 05.11.07 baseband. Go to setting => General => About

If you are running some older firmware then upgrade to firmware 3.1.2.

Step 1. Go to http://www.blackra1n.com/ url, download BlackRa1n depending upon your computer (PC or Mac). If you are downloading using safari then your download will be in zip format. Unzip it.

Step 2. Connect iPhone to the computer and make sure that iPhone is turned on.

Step 3. Double click on blackra1n icon that you downloaded in step 1.

Note: you may get warning depending upon your operating system after double clicking on blackra1n icon. Click on Run.

Step 3. You will see a large button (make it ra1n) on a window. Click this button.

Step 4. Your work is done now. Geohot will do the rest. iPhone will enter in recovery mode.

Step 5. Wait for 5 mins. You’ll see jailbreak done screen. Your iPhone will reboot now.

Step 6. Unlock iPhone and check your screen. Your iPhone is jailbroken. You’ll see blackra1n icon in your iPhone’s window. Tap on the icon.

Step 7. [Optional] Go to Setting => General => Auto-Lock and make this value Never.

Step 8. Choose installer you like most and choose snow if you would like to unlock your iPhone for all the carriers.

Note: You will need internet connection on your iPhone to perform step 8.

Step 9. Wait for some time. You will see a log window after all the installations are finished.

Step 10. If you want to remove blackra1n icon form iPhone then tap on uninstall blackra1n. You’ll see delete button. Tap on this button.

Step 11. [Optional] If you have changed Auto-Lock time in step 7, then reset this value to the value you like.

The iPhone Dev-Team has released new versions of QuickPwn and PwnageTool for the 2.2 iPhone firmware.

You can find our newly updated tutorials here (more to come):
- Jailbreak 3G (Mac) (Safe)
- Unlock/Jailbreak 2G (Mac) (Safe)
- Unlock/Jailbreak 2G (QuickPwn Windows) (Safe)
- Jailbreak 3G (QuickPwn Windows) (Unsafe if you want to unlock in the future)
- Jailbreak 2G/3G (QuickPwn Mac) (Unsafe for 3G if you want to unlock in the future)
To read in detail click here.

There are few paid video recorder available in iPhone. I tried one of them but was not happy with the quality and it takes too much time in saving video to the disk. Recently I tried cycorder, which is available free of cost. I like this recorder as it doesn’t take time in saving video. Quality of recorded video is awesome. You can’t expect better quality than this in 2 M Pixel camera.
To install cycorder, you must have jailbroken iPhone which is running firmware 2.0 or above. Go to cydia search option and type cycorder. Now install it like you installed other packages using cydia.

If you have updated your 2G iPhone to firmware 2.0 or later then you would have noticed that there is no Edge setting present and you can’t use Edge on such iPhone. Specially in case of jail broken iPhone, you might want to use edge connection to access internet. To enable edge, follow the instruction set
1. Make sure that you are able to connect your iPhone to WinSCP. Click here to know more.
2. Go to /private/var/mobile/Library . Now click on Carrier Bundle.bundle.
3. You’ll see carrier.plist file. Copy this file to your computer.
4. You need to edit carrier.plist file. In case if you are using Mac then it’s very easy as there are many editors available which can open .plist binary files in text format. If you are using windows then you may use http://iphoneinterest.com/view-plist-files link to see the content of the file.
5. Upload the file to above link (Mac users too).
6. You’ll see that you file is converted to xml format. Now you need to copy the converted content and save this content to carrier.plist file into your computer.
7. Open saved file in text editor.
8. Add following entries just below tag as shown in image. Save the files.

<key>AllowEDGEEditing</key>
		<true/>

9. Replace carrier.plist file in your iPhone from this newly created carrier.plist file.
10. Reboot iPhone and now go to Settings-> General -> Network. You’ll see Cellular Data Network in this page.
11. Provide network detail and enjoy edge.

MPlayer for iPhone supports mpeg4, h.264, wmv, mp3, aac, wma, real media, and t-dmb formats. It is good to have more supported movie formats for iPhone so that you don’t need to convert favorite movies to MP4 format before playing them on iPhone. To do that, you need to install MPlayer. Below are the steps to install MPlayer in iPhone
1. Make sure that yours is jailbroken iPhone as MPlayer is only available for jailbroken iPhones which have 2.0 or above firmware. So if your iPhone is having lower firmware version you need to update it to 2.0 or above.
2. Open Cydia installer app.
3. Update all the pending updates in Cydia installer.
4. Search MPlayer in search section of Cydia installer.
5. Tap on install button. It’ll install MPlayer in the iPhone
6. Connect iPhone to WinSCP and go to /private/var path
7. Look for media folder and if there is no media folder in this location then create one. This is the folder which will contain all the MPlayer’s playable files.
8. Copy movie files to /private/var/media directory.
9. Open MPlayer in iPhone. It will show you the list of all files present in above folder.
10. Tap on any file you would like to play.

PDANet from June Fabrics is very popular in windows based mobiles. It allows you to turn your smart phone into Wi-Fi router for your laptop. It is now available for iPhone.

Unlike other software like iPhoneModem, NetShare that tether your iPhone through SOCKS proxy solution, PDANet is true Wi-Fi router. This works seamlessly as if you are connected to a Wi-Fi router. You can share internet to as many terminals you want. You don’t need to configure any settings in your browser or you don’t require specifying any IP address. This is simply another Wi-Fi router.
The only negative point in this app is that you need to jailbreak your iPhone.