User selectable operating systems

1. A device comprising:

non-volatile primary storage having multiple compressed operating systems stored thereon in inoperable form with multiple respective digital signatures for the multiple compressed operating systems; and

a processor configured to execute a boot loader that is configured to:

receive a user selection of a selected operating system;

verify the selected operating system using an individual digital signature that is stored on the non-volatile primary storage for the selected operating system;

install a file folder structure on the non-volatile primary storage in a configuration specific to the selected operating system;

install the selected operating system in an operable form on the non-volatile primary storage relative to the file folder structure;

retain another compressed operating system in inoperable form on the non-volatile primary storage with the selected operating system in the operable form;

while the selected operating system is installed in the operable form and the another compressed operating system is stored in the inoperable form on the non-volatile primary storage, receive another user selection requesting a change from the selected operating system to the another compressed operating system; and

responsive to the another user selection, remove the operable form of the selected operating system from the non-volatile primary storage and install the another compressed operating system in operable form on the non-volatile primary storage.

2. The device of claim 1 , wherein the boot loader is the only boot loader on the device.

3. The device of claim 1 , wherein the boot loader comprises instructions that run on the processor before other instructions of the selected operating system.

4. The device of claim 1 , wherein the boot loader is configured to:

install the operable form of the another compressed operating system in a soft partition on the non-volatile primary storage.

5. The device of claim 1 , wherein the boot loader is unified extensible firmware interface (UEFI) compliant for each of the multiple compressed operating systems.

6. The device of claim 1 , wherein the boot loader is further configured to:

maintain an operating system vault on the non-volatile primary storage, the operating system vault having the multiple compressed operating systems stored thereon in inoperable form; and

prevent the operational form of the selected operating system from accessing the operating system vault.

7. The device of claim 1 , wherein the device comprises a smart phone, a tablet, a wearable smart device, or a personal computer.

8. The device of claim 1 , wherein the processor is further configured to send a message that indicates that the selected operating system was installed in an operable form.

9. The device of claim 1 , wherein the non-volatile primary storage comprises factory installed flash storage and wherein the inoperable forms of the multiple compressed operating systems are stored as a single binary file on the factory installed flash storage.

10. The device of claim 9 , wherein the single binary file is burned onto the factory installed flash storage during manufacture of the device.

11. The device of claim 1 , wherein the device is further configured to validate a digital signature of the boot loader before loading the boot loader on the device.

12. The device of claim 1 , wherein the selected operating system is not aware of the another compressed operating system on the non-volatile primary storage.

13. A device comprising:

a display;

a processor; and

persistent storage storing:

multiple operating systems in compressed form and multiple respective digital signatures for the multiple operating systems; and

computer-readable instructions which, when executed by the processor, cause the processor to:

while an operational form of a selected operating system of the multiple operating systems is installed on the persistent storage, cause a graphical user interface (GUI) to be presented on the display that lists another operating system of the multiple operating systems that is stored in compressed form on the persistent storage;

while the operational form of the selected operating system is installed on the persistent storage, receive, via the GUI, a user input identifying the another operating system stored in the compressed form on the persistent storage; and

responsive to the user input received via the GUI, delete the operational form of the selected operating system from the persistent storage and install an operational form of the another operating system on the persistent storage while retaining a compressed form of the selected operating system on the persistent storage.

14. The device of claim 13 , wherein the computer-readable instructions, when executed by the processor, cause the processor to:

obtain configuration data for the another operating system and write the configuration data to the persistent storage with the operational form of the another operating system.

15. The device of claim 14 , wherein the at least some of the configuration data relates to user settings.

16. The device of claim 13 , wherein the computer-readable instructions, when executed by the processor, cause the processor to:

responsive to the user input received via the GUI, install one or more soft partitions on the persistent storage and install the operational form of the another operating system in an individual soft partition.

17. A method comprising:

storing a compressed version of a first operating system and a compressed version of a second operating system in an operating system vault on a persistent storage device of a computing device;

receiving a first selection of the first operating system;

responsive to the first selection, installing an operable version of the first operating system on the persistent storage device while retaining the compressed version of the second operating system in the operating system vault on the persistent storage device;

while the operable version of the first operating system is installed on the persistent storage device, preventing the operable version of the first operating system from accessing the operating system vault on the persistent storage device;

receiving a second selection of the second operating system; and

responsive to the second selection, deleting the operable version of the first operating system from the persistent storage device, installing an operable version of the second operating system on the persistent storage device, retaining the compressed version of the first operating system in the operating system vault on the persistent storage device, and preventing the operable version of the second operating system from accessing the operating system vault.

18. The method of claim 17 , performed by a boot loader of the computing device.

19. The method of claim 18 , wherein the computing device is a mobile computing device and the persistent storage device is a factory-installed flash storage device, the method further comprising:

delivering the mobile computing device to an end user with both the compressed version of the first operating system and the compressed version of the second operating system stored in the operating system vault without any operable operating system version installed on the factory-installed flash storage device.

20. The method of claim 17 , wherein at least one of the first selection or the second selection is received via a graphical user interface.