About Android Recovery
All Android devices ship with a recovery console that is basically a partition on the device’s internal memory and can be booted into. The stock recovery of almost all Android devices provides a few basic yet handy options that allow you to factory reset your device, clear its cache partition, and recover its operating system using an official ROM in zip format, but that’s all you can do with it. That’s where a custom recovery comes handy.
A custom Android recovery basically replaces the stock recovery with one that lets you do all you can do with the stock recovery, plus a plethora of more options to give you a lot more control on your device. With a custom recovery, you can install official and unofficial ROMs as well as other updates including hacks, themes, kernels etc. using zip files, wipe not just user data but pretty much every standard partition on your device, mount the storage card for USB mass storage access without leaving recovery, partition your SD card, wipe dalvik cache and battery stats, fix permissions, perform, manage and restore backups, and so on.
Introduction to ClockworkMod
ClockworkMod recovery is one of the most widely used custom Android recoveries that is available for most mainstream Android devices. It is our custom recovery of choice here at AddictiveTips and almost every custom ROM that we install on our devices is done using this recovery.
ClockworkMod recovery has been developed by Koushik Dutta (also known as Koush) – the same guy who brought us the Android ROM Manager. He can be found at his blog hacking away at Android devices, and at Twitter.
For most devices, ClockworkMod has a dead simple installation process. This method does require you to fully root your device in order to be installed but once rooted, installing it is as simple as installing ROM Manager from Market, launching it and using its first option i.e. the one that says ‘Flash ClockworkMod recovery’.
However, in certain scenarios, the ROM Manager method wouldn’t work, or would simply not be the preferred method for your situation. In such cases, there are several other methods available to install ClockworkMod. We have covered the ROM Manager method as well as all these alternative methods in our guide on how to install a custom recovery to your Android device.
Booting into ClockworkMod
Also, if you have ADB installed on your computer, you can simply enable USB debugging mode on your device from Settings > Applications > Development, connect it to your computer via USB, launch a Command Prompt / Terminal window on your computer and enter this command:
adb reboot recovery
The above methods will not work in certain cases though, for instance if you can’t boot into Android in the first place due to some issue, or if you are using a device like the HTC HD2 that doesn’t natively support an Android recovery. Many solutions are available in these cases.
Using hardware button combination on most Android devices:
On most Android devices including ones by HTC, you can enter recovery by powering your device off and then powering it back on while keeping either the ‘Volume Down’ or the ‘Volume-Up’ button pressed, depending on the device. This will enter the bootloader from where you can select the ‘RECOVERY’ option by navigating to it with the Volume key and entering it with the ‘Power’ key.
On most Samsung devices specifically Samsung Galaxy S series devices, you must keep both the ‘Volume-Up’ and ‘Home’ keys pressed while powering on the device, to directly enter recovery.
Using MAGLDR on HTC HD2:
Entering ClockworkMod recovery on the HTC HD2 can’t be done via ROM Manager or any hardware button combination but that doesn’t mean it is difficult in any way. All you have to do is power the device off, power it on by keeping the Power key pressed till you see the MAGLDR bootloader’s menu and finally selecting the ‘AD Recovery’ option.
Now that you have ClockworkMod recovery up and running on your phone or tablet, let’s take a look at all the options it offers you to manage your Android device. We are using a Nexus S running ClockworkMod Touch recovery 184.108.40.206 but the details should apply to other devices and versions of the recovery as well.
This is what you see when you reboot your device into ClockworkMod recovery:
If you are using ClockworkMod Touch recovery, you can simply tap on these options to navigate between different sections and perform all the actions. On the non-touch versions of the recovery though, you can navigate between items using the Volume-Up and Volume-Down button, and use the ‘Power’ button to enter/launch the highlighted option on most Android devices. On devices equipped with a trackball or an optical track pad such as the G1, G2, Nexus One, HTC Desire etc., the trackball or track pad can be used for navigation and clicking it activates the selected option. Let’s review each of these options and their sub-menu options in detail now.
1. Choose zip from sdcard
2. Apply /sdcard/update.zip
3. Toggle signature verification
4. Install zip from sideload
5. Wipe data/factory reset
6. Wipe cache partition
7. Backup and Restore
- Backup:- Takes a full backup of your device, as explained above.
- Restore:- Lets you restore a previously taken backup. Entering this option presents you with a list of existing backups from the SD card that you can choose from for restoration
- Delete:- Lets you delete a previously taken backup to free up space on your SD card.
8. Advanced restore
9. Free unused backup data
Lets you reclaim space on your SD card by freeing up any redundant backup data that isn’t required.
choose default backup format
Allows you to choose between ‘tar’ and ‘dup’ for the backup format. Leave this one as it is, unless you are sure you want to change it.
10. Mounts and storage
Allows you to perform maintenance tasks on all the internal and external partitions of your android device
11. mount/unmount /system, /data, /cache, /sdcard or /sd-ext
These options let you toggle between mounting or unmounting these respective partitions. Most users don’t need to change these options.
12. Format boot, system, data, cache, sdcard or sd-ext
These let you directly format any of these partitions. Take extreme care with this option as formatting any of these partitions will result in losing all data on them, especially the boot and system partitions. Formatting the system partition will remove your ROM and leave your phone without an operating system while wiping the boot partition may brick your phone unless you restore or flash another one before rebooting your device. To learn more about the contents of all these partitions, see our guide to Android partitions.
13. Mount USB storage
Lets you enable USB mass storage mode for your SD card right from recovery so that you can connect it to your computer via USB and transfer any files to/from it without having to leave recovery.
This section contains a few options most users will not require, though these can come handy quite often, especially wiping Dalvik cache, which is required before most ROM installations. Here are the options from this section:
- Reboot recovery:-Lets you directly and very conveniently reboot from recovery right back into recovery. This is useful option for certain back-to-back installations that require the device to at least boot once between them.
- Wipe dalvik cache:- Allows you to wipe the cache for the Dalvik virtual machine (the custom-built Java virtual machine for Android).This is required before most ROM installations and at other occasions too, for fixing some problems.
- Wipe battery stats:- Wipes the saved battery usage statistics and effectively recalibrates the battery. Useful in various scenarios when Android isn’t showing correct battery levels. This option is not shown in the above screenshot, but is present in many versions of ClockworkMod recovery.
- Report error:- In case of errors, this feature can be used to save a log of recent ClockworkMod recovery operations on the SD card that you can later report from Android using ROM Manager.
- Key test:- Lets you press any of the hardware keys to see if they are properly functioning, and to see their key codes.
- Show log:- Shows you a log of your recent recovery operations.
- Fix permissions:- Fixes the file permissions for the internal memory partitions back to default. This is very useful as a fix for several errors and Force-Closes that start appearing after you or an application you installed and provided root access end up messing up the permissions of important files.
- Partition sdcard:- This option gives you a no-frills way to partition your SD card properly for use with ROMs that support data2ext (a very handy hack for low internal memory devices that enables an /sd-ext partition on the SD card to be used as the internal user data storage i.e. as the /data partition). Once this option is selected, you will be given options to choose the sizes for the /sd-ext partition as well as an optional /swap partition on the SD card, and will then automatically format it for you, leaving the remaining space for normal SD card usage. This option will wipe all data from your SD card so use it with caution!
Using ClockworkMod for ROM, kernel, apps, theme or mod installation
While in the complete feature tour we have already shown you how to install a ROM, kernel, app, theme or any similar mod from a recovery-flashable zip file using the recovery options, those of you who jumped straight to this section expecting to get just this information quickly are at the right place!
This guide is primary focused on a full feature tour of ClockworkMod recovery but in our previously written guide on how to flash a ROM or app from a zip to an Android device file from recovery, we have already covered in detail how to use ClockworkMod for installing any ROM, kernel, app, theme or mod using a recovery-flashable zip file. While that guide is based on an older version of ClockworkMod recovery, everything in it still applies to the latest versions and should work flawlessly.