As I understand it, the Slax Android app will not offer an ARM port of Slax that will run as the operating system for the phone/tablet. Rather, it will be a way to download the intel-compatible version of Slax (I don't know if it's i486 or x86_64) and place the files onto the phone such that you can plug the phone into a computer, and then boot the computer into Slax, using the files on the phone (instead of booting off a flash drive).
I've never tried it, but I imagine this functionality is already possible with Porteus so long as the computer supports booting via usb and the sdcard storing the Porteus data can be made bootable and is detected by the computers' BIOS through the phone (basically, you're using the android phone as a very expensive sdcard->usb adapter). The only thing we're missing is an android app to copy the files and install the bootloader. Given that I'm not an android developer and this can be accomplished for Porteus nearly as easily as installing to a USB drive, I don't have plans to create and distribute such an application.
"Porting" Slax or Porteus to ARM architecture is another story entirely, and this is what I did on my tablet. In this case, the tablet's hardware boots and runs Porteus natively, and I can dual-boot it with android. I would not recommend this for the current generation of phones, for a couple of reasons: first, even on my dual-core 1Ghz ARM processor with 1GB of RAM, the system (running Xfce 4.10) is already not as responsive as I would like. Secondly, I haven't found a virtual keyboard application that I think would be useable when scaled down to the size of a phone. Tablets are another story; I think there might be a market there, but for the most part, this is a novelty for hardcore linux fans. Realistically, it's going to be hard for someone like me (more or less by myself) to develop an operating system that can compete on a broad basis with Android.
There is a third option -- running linux within a 'chroot' environment under Android. There are apps on the google play market to install ubuntu on your android device, and this is what they are doing. They copy a linux system (compiled for ARM) onto the device, then they setup a 'chroot' environment within Android which boots up linux, and then you can swap over to the linux system, rather like running it inside a virtual machine. This doesn't satisfy my needs for two reasons: first, you're using system resources already to run Android, and then using even more to run linux, so you're bound to run far slower than a 'native' installation. Second, when you're running this way, the android kernel is actually running the linux OS (chroot doesn't boot a new kernel, it runs everything from the existing kernel as if the 'chroot folder' is /). The android kernel (as far as I am aware) does not include the aufs patch, which is required for Porteus to run 'live'. So unless I could patch and replace the android kernel (and a different kernel would be required for each and every android device), all I could really install is a slimmed-down Slackware.
Sorry for going off on a million tangents here...
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