This is the experience of a friend solving Wi-Fi connection issue on his iPad mini.
He bought a iPad mini Wi-Fi model last December and has been happily using it in his home network until last week. Suddenly the network connection became slow, way too slow to be usable. He was able to get web pages to load only when the iPad mini was within 1 metre of the Wi-Fi router.
He did a network speed test using the Speedtest.net app and found out that the speed had drop below 1Mbps for both upload and download. Normally the Wi-Fi speed is between 10Mbps – 25Mbps in his home network.
To make sure there were nothing wrong on the Wi-Fi router, he tested the connection speed using a iPhone 5, a MacBook Pro and a Windows notebook. All devices’ Wi-Fi were working normally except for the iPad mini.
To troubleshoot further, he upgraded the iOS from 6.1.2 to the latest 6.1.3, but it did not solve the problem. He tried to reset the network settings next from Settings > General > Reset > Reset Network Settings. Still, the Wi-Fi connection persisted.
He then backed up his iPad mini’s data, and did a complete wipe using Settings > General > Reset > Erase All Content and Settings. And his woe continued despite all the steps he tried.
So he brought the iPad mini down to Apple. The staff did a simple check on the iPad mini, and within less than a minute informed him that Apple would do a one-to-one exchange of his iPad mini. Judging from the quick diagnostic from Apple support staff, it appeared to be a common issue. A quick search on the web suggests that this issue might affect only the first batch of iPad mini.
If you encounter similar Wi-Fi issue on your iPad mini, do not despair. There is no need to buy an additional Wi-Fi signal booster. Just back up your data and bring the unit down to Apple for a free replacement as iPad mini is covered by a one year warranty. That is the only way to solve the Wi-Fi problem.