[Nexus One Android Development] madmaxx82:
Recovery is free (of course ! ) and has nothing to do with any apps!

You can compare the app's features on www.4ext.net.

Free "Updater" app:

browse all versions of 4ext recovery

flash or download any version directly verifying md5sums automatically.

view changelogs / known issues while downloading

get news if any new critical bugs are found

send bug reports where you can include your last recovery log by ticking an option if you wish.

This App is a great time saver for me as I can add things to known issues if any very quickly for all devices, or send a notice that something was discovered, that you should know about (like a new bug found in a version released the day before or something).

I also increase the chance that people read the change logs or known issues, because they are immediately and easily accessible!

"Control" app: quite much, please see www.4ext.net

To be able to test all features of the "full version" app (which has nothing to do with recovery itself!),

the "Updater app" includes a full featured 3 day preview with all features of the paid one.

After that, it is just the free version.

There are no ads, or any other bull**** ;)

About the recovery features and why to use/not to use it over any other recovery, please see 1st post:

Features:

Use 4EXT Recovery Control or Recovery Updater for complete Changelogs and Known issues!

not all features may be relevant for all devices

Displays additional information:

Identifies your current rom and displays its name

Current filesystems on your partitions

Free space remaining of all of your volumes

Current battery charge level

Backup | Restore:

Correctly calculates free space needed to complete a backup ( version > 2.2.6 RC4 )

Tar backups (can be switched on or off)

Complete CWMR5 compatibility

All Backups you create will be named after your currently installed Rom for easier identification.

Never unwillingly get "downgraded" to EXT3 again

Always restores backups using the file systems you HAD on your partitions at the time of creation!

-> all partitions formatted with ext4 at that time, will be restored to ext4. The same is true for ext3.​

You can manually change any existing Backup to ext4 or ext3

-> so that after a restore, all partitions and up with the file system you wanted!​

Advanced Backup: backup only a single partition

Convert any of your partitions to EXT4 or EXT3 without data loss.

Formatting:

When you wipe or format it will always use the same file system you currently have.

-> but you can change that​

When you format ext4 it will always create an aligned file system

Correctly identifies unformatted sd-ext partitions

-> if it finds one it displays a warning and suggests you may format them by visiting the 4EXT menu​

Filesystem check and repair option in advanced menu

Partitioning:

Alignment check of your partitions

Full support for up to 2 sd-ext partitions + swap (Backup/restore/format/convert, fsck, et.c.)

(RE-) Partition your sdcard for sd-ext without removing your fat32 partition.

All partitions created with 4EXTRecovery will be perfectly aligned to 4k

Installing:

Integrated md5sum checking option

Themes:

Customize all colours used throughout recovery

Use your own icons, background images, progress bars.. more to come.

Assign different backgrounds to different menu categories (version >= 2.1.2)

Create a flashable zip for others to flash your theme.

Menus:

Most popular menu items rearranged

Format menu

Power Menu + option to reboot into bootloader

Less "No's" in confirmation dialogues

Changed Advanced Restore: first select what you want to restore, then select the backup

-> Useful for restoring from "Advanced Backups"​

4ext.prop:

Configuration file on your sdcard where you can set options to be used by 4EXTRecovery

Change all settings conveniently with 4EXT Recovery Control

Many more options to come

Share your settings / themes by packing your config into a flashable theme

Other stuff:

USB Storage Autostart (must be switched on)

Mount usb storage exposes all partitions on your sdcard to the os (not just fat32)

-> you could even partition your sdcard from your PC while connected via USB​

Switch haptic feedback on/off

You don't need to reboot recovery if you transferred a file to show up in the install menu.

-> This bug affected only some users with either CWMR or previous versions of 4EXT.​

Button backlights (Desire S, Desire HD and Incredible S only)

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