Several problems have been reported with the Apple iPad in that some say it is over heating, some say WiFi connectivity is having issues and some say they have power issues after switching off.
Apple [AAPL] have responded to the WiFi issues and provided a set of instructions of how to fix wifi on the Apple iPad. Basically they say the issues can be caused by dual-band routers where they suggest splitting the bands to make it easier. Another suggestion mentions resetting the network settings on the iPad and the final idea is to double check the firmware on the router you are connecting to, to make sure it's running the latest.
Of course it's a hard one to track down, but with many different routers being available, some will have issues. I know from my own experience that an old D-Link router I had used to cause wireless networking issues with some devices that connected to it.
Here is the full set of instructions from Apple [AAPL] to help you resolve the issues...
Symptoms:
Under certain conditions, iPad may not automatically rejoin a known Wi-Fi network after restart or waking from sleep. This can occur with some third-party Wi-Fi routers that are dual-band capable when:* Using the same network name for each network
* Using different security settings for each networkResolution:
If you encounter this issue, try the following:* Create separate Wi-Fi network names to identify each band. This can be done easily by appending one or more characters to the current network name. (Example: Add a G to the 802.11b/g network name and an N to the 802.11n network name.)
* Ensure that both networks use the same security type (WEP, WPA, WPA2, and so on)
* If the issue persists, reset your network settings using Settings > General > Reset > Reset Network Settings.Note: Always ensure that your Wi-Fi router firmware is up to date.




