DFU stands for the Device Firmware Update, it is that state of your iDevice when it doesn’t load the Operating system on itself but still can be interacted with iTunes. It is pretty much different from the Recovery mode because it bypasses the bootloader on your iPhone, iPod Touch and iPad.
Uses of DFU Mode:
Apple doesn’t allow downgrading to previous versions of iOS; this is where DFU mode comes in handy. It allows you to downgrade to previous versions of iOS, so you can Jailbreak your iDevice, install custom firmware or can unlock your iPhone.
For example: If you have installed iOS 6.1.4 on your iPhone and you want to downgrade your iPhone to previous versions to get the Jailbreak, you will need to enter in DFU mode. On the other hand, Device compatibility and downgrading softwares are also needed to install previous versions of iOS.
How to Enter in DFU mode:
The most important thing before entering in DFU mode is the timing; you should hold the buttons for exact time as mentioned below. Otherwise it will lead to recovery mode instead of DFU mode. You can follow these simple steps to enter in DFU mode.
1. Launch iTunes on your PC and connect the iPhone using USB Cable.
2. Turn Off your iPhone, iPod Touch and iPad while connected with PC or Mac.
3. Press and hold the Sleep button (located at the top of your iPhone) and Home Button for exactly 10 seconds.
4. After 10 seconds, releases the power button while keep holding the Home button until the following message appears in iTunes.
5. Your iPhone, iPod or iPad will have black screen which indicates that your iDevice is in DFU mode.
You can easily interact with your iDevice from iTunes to install new custom firmware, Jailbreaks or downgrades. If your iDevice shows another message other than black screen, it indicates that your iDevice is not in DFU mode.
How to Exit from DFU Mode:
Exiting from DFU mode is rather simple as compared to enter in it. Carefully follow these steps:
1. While connected to PC, Press and hold down Sleep and Home button till the Apple Logo Appears on the screen of your iDevice.
2. Release the both buttons so that your iDevice disappears from iTunes.
3. Now, Press the Sleep button and your iDevice will be restarted normally.
Unlike DFU mode, Recovery mode is pretty simple and it can be defined as the state in which iPhone loads the bootloader but not the OS. However, it can still be interacted with iTunes to install fresh firmware and restores.
Uses of Recovery Mode:
Recovery mode doesn’t allow you to downgrade previous versions of iOS. However, you can simply restore your iPhone, iPod Touch or iPad to current firmware or install the updates using the Recovery mode. On the other hand, Recovery mode may also be useful to Jailbreak your iPhone, iPod Touch or iPad.
How to Enter in Recovery Mode:
Entering Recovery mode is pretty easy and simplest process. Just follow the simple steps:
1. Connect your iPhone with PC via USB cable and open iTunes.
2. Now, Press and hold the Sleep button till the “Slide to Power Off” appears on the screen of iPhone.
3. Slide to turn off your iDevice.
4. Once your iDevice is turned OFF, Press and hold down the Sleep/Power and Home button.
5. Once Apple logo appears on your iPhone, leave the Sleep button while holding the Home button on your iPhone. Keep Holding the Home button until you see the “Connect to iTunes” on your iPhone.
Once your iDevice is in Recovery Mode, you can update the iOS or restore the currently installed firmware on it.
How to Exit from Recovery Mode:
Sometimes iDevices get stuck in the Recovery mode; you can easily exit from Recovery mode by following these steps:
1. While connecting your iPhone with PC, Press and hold the Sleep and Home Button for about 15 seconds which will completely turn off your iPhone.
2. Now, Press the Sleep Button again to turn off your iPhone.
If this method doesn’t solve your problem, you will need to restore the latest iOS version on your iDevice.
Similarities and differences between DFU and Recovery Mode:
1. Both modes can be used to restore the latest version of iOS on iPhone, iPod Touch, iPad and iPad mini.
2. Both modes are easily returnable using the same methods as explained above.
3. DFU mode is a necessary step for Jailbreaking iPhone, iPod Touch or iPad using Redsn0w as the Jailbreak Software. While Recovery mode is necessary for installation of new firmware.
4. DFU mode can also be used to downgrade to previous versions of iOS but Recovery mode can’t.
5. Recovery mode doesn’t bypass the bootloader on iDevices while DFU mode can easily bypass the Bootloader and prevent loading the default OS on iDevice.
Both the DFU and Recovery Mode are very useful to install custom firmware, update, unlock or Jailbreak iPhone, iPod Touch or iPad. Entering or exiting from DFU or recovery mode depends upon the timing of pressing the Sleep and Home Button. Pressing home button for too long may lead to recovery mode instead of DFU mode.