Q: cannot join wi fi network

Hello there drewt123,

Thank you for using Apple Support Communities!

It sounds like you are having some wifi connectivity issues after updating to iOS 7.0.2

I want to recommend this article named:

iOS: Troubleshooting Wi-Fi networks and connections

http://support.apple.com/kb/TS1398

1. Be sure you're in range of your Wi-Fi router (access point).
2. Tap Settings > Wi-Fi and turn Wi-Fi off and on. If your W-Fi setting is dimmed, follow these steps.
3. Confirm that your Wi-Fi router and cable or DSL modem are connected to power, turned on, and connected to the Internet. If not, refer to your network administrator or Internet service provider (ISP) for assistance.
4. Restart your iOS device.
5. Tap Settings > Wi-Fi and locate the Wi-Fi network to which you're connected.
6. Tap and Forget this Network.
7. Try to connect to your desired Wi-Fi network.
   Note: You may need to enter your Wi-Fi password again if your network requires one.
8. Turn your Wi-Fi router off and on². If your ISP also provides cable or phone service, check with them before attempting this step to avoid interruption of service.
9. Update your device to the latest version of software.
10. Update your Wi-Fi router to the latest firmware². For AirPort Base Stations, install updates using the AirPort Utility.

If that does not resolve your issue, I would next follow either of these 2 sections from toward the bottom of the article depending on the situation.

Unable to locate a Wi-Fi network

Unable to connect to a Wi-Fi network

Regards,

Sterling