How do I convert ASEC files to APK? Is there anyone that knows how I can convert ASEC files to APK?
According to this question/answer, the .asec files are actually dm-crypt containers which can be mounted, and contain the unencrypted .apk. The keys are stored in /data/misc/systemkeys/AppsOnSD.sks.

The mounting process depends on the tools available, but it can be as simple as running (on Linux) losetup /dev/loop0 /path/to/file &amp;&amp; cryptSetup open --type luks -d /path/to/keyfile /dev/loop0 asecmount &amp;&amp; mount -t ext4 /dev/mapper/asecmount /your/mountpoint to mount and umount /your/mountpoint &amp;&amp; cryptsetup close asecmount &amp;&amp; losetup -d /dev/loop0.

You can also access the contents of the .asec file from /mnt/asec/[app-id]/ if you have it already mounted on your device.