By rooting (aka gaining admin rights to) your Nexus 7 2013, you can install a custom ROM, run rooted apps, undervolt or overclock the processor, and even add multi-window support (like the function on the Galaxy Note 3) to the Nexus 7 2013. A developer called WugFresh created (and continues to update) a program that allows you to root, flash a custom recovery, and even unroot any Nexus device. Here we'll how you how to use it on the Nexus 7 2013.
This program only works on Windows.
1. Head to the developer's site here and download the toolkit under Downloads.
2. Double click the .exe file and install the program.
3. Select the Nexus 7 v2 that you have when prompted and choose the version of Android and Build you currently have (you can check this by going to Settings > About Tablet and looking there).
4. Go to Settings > About Tablet.
5. Tap Build over and over until it tells you you are a developer.
6. Go to Settings > Developer Options.
7. Turn on USB Debugging.
8. Plug in the device via USB cable.
9. Open the Toolkit on your computer (if it isn't already).
10. Tap Unlock in the toolkit and wait for the device to reboot.
11. Select Yes on the device when prompted by pushing volume up then power. The program will continue and the device will reboot.
12. Go through the setup process as normal until you get to the home screen.
13. Re-enable USB debugging by going to Settings > About Phone.
14. Tap Build over and over until it tells you you are a developer.
15. Go to Settings > Developer Options.
16. Turn on USB Debugging.
17. Plug in the device (if it isn't already).
18. Check the box for Custom Recovery and click Root in the toolkit. Wait for it to finish. The device will reboot.
19. Check to see if you have superuser in the app drawer, if so, you're all set!
David Cogen is a founder of TheUnlockr.com, the popular site for rooting, jailbreaking, hacking, modding, and other how tos to show you how to unlock your device's true potential. They even have a popular ROM repository. Check out TheUnlockr.com for all your Android, iPhone, and Windows Phone how tos.