If you didn't fix your problem yet .. Then you should know that Apple store sell you a new fake used device. I had the same problem last year .. I took my device to there office and the told me your device has signal but it is week .. They ask my to up date it and delete some apps. Unfortunately the home button now is not working and the warrantee expired. I bought the button from eBay and when I open the device I realize that this device had been open before and missing some screws. How that could happen, I bought it as a new device from Apple store. Surprisingly, it was missing the WiFi antenna, which I'm going to order it today from eBay.
My small advice to you .. Go Samsung ..
If you make such outrageous claims, would you please NAME the Apple Store you bought that particular "used" device from and the date? I am sure you still have the receipt somewhere.
I am sorry but I don't believe you a word, especially after the Go Samsung comment at the end of your post.
I bought it from Apple store at Pacific Center, Vancouver, BC. Canada.
And my advice was because I took the device to apple store and they didn't help me until the warranty expired and after the warranty expired by one day I went to them again for the same problem they ask me to pay 300$ to change the device.
I was really disappointed.
I have had similar issues on an ipad3 64Gb. Poor wi-fi signal when outside the room that the router is located. Only two bars in the same room. New fibre optic router with latest software. Also checked on two different networks. Did a side by side test with an ipad 2 (which managed to get a perfect signal in the same location).
Did a hard network reset - no effect.
Did a full system restore - setting up as a new ipad - no effect.
Looks like it will have to go back for a service.
One thing to try which seemed to clear up some really bad connectivity issues I had was to go onto the router and reserve an ip address. You don't need to set it as static on the pad as well, but also worth a shot.
I was getting little to no data transfer between the hub and the pad though my ipad2 was fine.
I first tried this on my iphone4s which fixed connectivity problems for it 2 years ago, so I now by default do this for any wifi device.
After doing it for the air, it seemed to smooth out a lot of issues.
However, I'm still getting poor throughput when streaming from youtube and terrible performance when using my kingston MobileLite wifi streamer. The ipad2 and 4s phone will happily play a 2gb movie over the wifi, but the ipad air can hardly even load a 3mb .MOV...