I recently tried to install the latest build on Rasher's Android Port, unfortunately, it didn't work and the app kept force closing so I look through the backups of my SD Card and found a working build that I had a while ago. Some people on the IRC channel suggested me to post a link to it here, so I did.
Here you go guys and have fun with Rockbox on your android phone.
https://docs.google.com/file/d/0B1oM6EEbUjlJaGEzRVJfTUdtM2s/editP.S.: The resolution is 480x800. Sorry for most of the users with HD displays
EDIT: As of this writing (20140825), this is no longer required, binaries generated from git head are functional on any Android device from 2.1 to 4.4.4, using the Dalvik runtime. ART runtime still causes a stack overflow, but this is of little to no concern as no devices currently exist that use the ART runtime so the user must make a conscious decision to use it and must accept the consequences thereof. - [Saint]