Protecting personal information upon sharing a personal computing device

1. A method comprising, by a computing device:

receiving authentication information provided by a temporary user, wherein the authentication information comprises login credentials that the temporary user uses to log into a social-networking system;

retrieving personal information associated with the temporary user from a server using the authentication information;

presenting a personalized user interface on a screen of the computing device for the temporary user, the personalized user interface being generated based at least in part on the personal information associated with a social-networking account of the temporary user on the social-networking system;

detecting a terminating event that indicates access to the computing device by the temporary user is to be disabled, wherein the terminating event is detected by receiving a communication via a network on the computing device that is targeted to a primary user of the computing device other than the temporary user currently using the computing device;

removing, in response to the detected terminating event, information associated with the temporary user from the computing device; and

reverting the computing device to a default state.

2. The method of claim 1 , wherein the communication comprises an incoming phone call or text message.

3. The method of claim 1 , wherein the terminating event is further detected by determining that the temporary user attempted to access protected or disabled data stores of the computing device.

4. The method of claim 1 , wherein the terminating event is further detected by determining that a predetermined timeout period expired while the temporary user is using the computing device.

5. The method of claim 1 , wherein the terminating event is further detected by determining that the computing device is put down.

6. The method of claim 1 , wherein the terminating event is further detected by determining that a biometric information associated with the temporary user is undetectable.

7. The method of claim 6 , wherein the determining that the biometric information is undetectable comprises one or more of:

detecting that a fingertip or palm of the temporary user is removed from an area of the computing device intended for providing constant biometric identification;

detecting that a camera of the computing device is no longer able to perform facial recognition of the temporary user; or

detecting that a scanner of the computing device is no longer able to scan an iris or retina of the temporary user.

8. One or more computer-readable non-transitory storage media embodying software that is operable when executed to:

receive authentication information provided by a temporary user, wherein the authentication information comprises login credentials that the temporary user uses to log into a social-networking system;

retrieve personal information associated with the temporary user from a server using the authentication information;

present a personalized user interface on a screen of the computing device for the temporary user, the personalized user interface being generated based at least in part on the personal information associated with a social-networking account of the temporary user on the social-networking system;

detect a terminating event that indicates access to the computing device by the temporary user is to be disabled, wherein the terminating event is detected by receiving a communication via a network on the computing device that is targeted to a primary user of the computing device other than the temporary user currently using the computing device;

remove, in response to the detected terminating event, information associated with the temporary user from the computing device; and

revert the computing device to a default state.

9. The media of claim 8 , wherein the communication comprises an incoming phone call or text message.

10. The media of claim 8 , wherein the terminating event is further detected by determining that the temporary user attempted to access protected or disabled data stores of the computing device.

11. The media of claim 8 , wherein the terminating event is further detected by determining that a predetermined timeout period expired while the temporary user is using the computing device.

12. The media of claim 8 , wherein the terminating event is further detected by determining that the computing device is put down.

13. The media of claim 8 , wherein the terminating event is further detected by determining that a biometric information associated with the temporary user is undetectable.

14. The media of claim 13 , wherein the determining that the biometric information is undetectable comprises one or more of:

detecting that a fingertip or palm of the temporary user is removed from an area of the computing device intended for providing constant biometric identification;

detecting that a camera of the computing device is no longer able to perform facial recognition of the temporary user; or

detecting that a scanner of the computing device is no longer able to scan an iris or retina of the temporary user.

15. A system comprising:

one or more processors; and

one or more computer-readable non-transitory storage media coupled to one or more of the processors and comprising instructions operable when executed by one or more of the processors to cause the system to:

receive authentication information provided by a temporary user, wherein the authentication information comprises login credentials that the temporary user uses to log into a social-networking system;

retrieve personal information associated with the temporary user from a server using the authentication information;

present a personalized user interface on a screen of the computing device for the temporary user, the personalized user interface being generated based at least in part on the personal information associated with a social-networking account of the temporary user on the social-networking system;

detect a terminating event that indicates access to the computing device by the temporary user is to be disabled, wherein the terminating event is detected by receiving a communication via a network on the computing device that is targeted to a primary user of the computing device other than the temporary user currently using the computing device;

remove, in response to the detected terminating event, information associated with the temporary user from the computing device; and

revert the computing device to a default state.

16. The system of claim 15 , wherein the communication comprises an incoming phone call or text message.

17. The system of claim 15 , wherein the terminating event is further detected by determining that the temporary user attempted to access protected or disabled data stores of the computing device.

18. The system of claim 15 , wherein the terminating event is further detected by determining that the computing device is put down.

19. The system of claim 15 , wherein the terminating event is further detected by determining that a biometric information associated with the temporary user is undetectable.

20. The system of claim 19 , wherein the determining that the biometric information is undetectable comprises one or more of:

detecting that a fingertip or palm of the temporary user is removed from an area of the computing device intended for providing constant biometric identification;

detecting that a camera of the computing device is no longer able to perform facial recognition of the temporary user; or

detecting that a scanner of the computing device is no longer able to scan an iris or retina of the temporary user.