Back in the day, I used to remove files from the Java folder by hand. Trouble is, I'm getting old and kept forgetting which filenames I needed to delete. I had a couple of disasters caused by me removing the wrong files that resulted in my BlackBerry coming out of an OS upgrade as a paperweight with a white screen.
I had the idea of making up old DOS batch files to do the job for me and this grew into CrackMem version 1.0 which had a quite archaic user interface. Many revisions later and we have the familiar sky blue panel of CrackMem 3.x and up.
CrackMem was designed to try and make it easy to save memory when upgrading and it has now grown to support a number of BlackBerry devices and OS versions.
The program now handles up to nine BlackBerry OS and will remove a wide variety of modules from the OS. It is important to note that CrackMem does not remove modules and files directly from the phone. CrackMem only ever (apart from Vendor.xml) works with files on your PC hard disk and never on your phone. That responsibility belongs to Desktop Manager and you should use CrackMem to condition your new OS before you put it on your phone. If you run into trouble upgrading then you can use the program to brick your phone back to JVM 507 by using the Wipe Device button. This uses the RIM Loader program and will wipe the phone and then begin the OS load process immediately after the wipe.
Obviously the preferred way to upgrade is via Desktop Manger and there is a button to run that too.
CrackMem is continually being upgraded as new OSs and BlackBerry devices are released. Each new release builds on the previous version and nothing is taken out.
CrackUtil is the next step along from JL_Cmder. Like JL_Cmder it is just a front-end for the RIM program Javaloader. CrackUtil is prettier and it's "killer feature" is the built in File Manager which allows you to remove or even add files to or from you BlackBerry.
When you run the program it asks for a phone password. If you have one, it only remembers it for the current session. If you don't have one then click either button.
Most of the Javaloader functions are there and the program is split into three screens. Opening the program after the password screen brings you to a screen where you can press any of the buttons and nothing bad will happen to your phone. The worst you can do here is to delete the phone's log file.
There are buttons for
- Set Device Time (set the time to that of the PC)
- Take Screenshot (what it says, really)
- Retrieve Event Log (just like Alt-LGLG)
- Clear Event Log (same a Alt-LGLG, Menu, Clear Log)
Screen2 is the File Manager and here you can Add or Remove files from your phone. Interestingly files you remove are not actually deleted. They are stored, due to a quirk of Javaloader, in the CrackUtil folder so that you can put them back again if you wish and have not crashed your phone.. This screen is really unique to CrackUtil and is really the reason that the program got written.
There's only three buttons and they are
- Retrieve File Listing
- Remove File From Device (and saves it to C:\Program Files\CrackUtil)
- Load File to Device (puts a specified file on the phone)
The final screen is just a push button JL_Cmder. You can wipe your device or remove a residual IT Policy but only if you are running OS 4.3 or better. On the other hand, this is the screen where you can brick your phone very quickly.
Again there are three buttons to play with.
- Wipe Device Applications (same as Options, Security Options, General Settings, press Menu, select Wipe Handheld)
- Wipe Device File System (Back to JVM 507)
- Reset IT Policy (for OS better than 4.3)
CrackUtil is a really handy utility that, in the right hands, can help you really optimize your phone. If you remove a theme, for example, it uninstalls it from the phone as well as removing it. In reality kudos go to RIM and Javaloader for this.
Use CrackUtil badly and remove the wrong file from your phone and you may just have a plastic brick sitting in front of you.