Dual booting on a device, be it a phone or tablet, brings forth some pretty substantial benefits. In addition to simultaneously and effortlessly switching between two ROMs, you also no longer have to wipe everything in order to try a new one. This, in and of itself, allows for more fun and experimentation to be had. After seeing dual boot on the Note 2, it was only a matter of time before something similar would pop up on the Galaxy S 4.
Thanks to the initiative of XDA Senior Member Grarak, a mod has been created that allows you to dual boot ROMs without having to wipe any data or make any backups. The primary ROM must be stock TouchWiz, while any AOSP-based ROM can fill in the second spot. By default, you should be running the Perseus Kernel, which the aforementioned Note 2 owners may be familiar with. However, this can be changed later. As explained by Grarak, the method is reliant on the mod switching between the two kernels that you will have installed.
It can’t be said that the initial setup of the dual boot method is a particularly easy process. However, it is relatively straightforward, and most folks wouldn’t experience much trouble when following the instructions posted. The mod is still in alpha stage, but Grarak is claiming that it is stable enough for everyday use.
If you’ve been looking to dual boot on your Galaxy S 4, head over to the development thread for more information and discussion._________