ScaraOS isn't just an app, it's an operating system. The author, Gianni Tedesco, has this to say about it:
"ScaraOS is a 32bit mutiboot OS kernel for IA32 (PC/AT) systems. I wrote it to teach myself OS fundamentals and just to have a bit of fun. It already has PCI support, the beginnings of a paged memory management system, and the start of a VFS layer. It supports the basic PC/AT stuff such as timer, PIC, keyboard, floppy."