Wi-Fi very poor with iPhone 4s?

I recently got a used iPhone 4s in perfect condition and everything works fine. Its just the Wi-Fi that does not work as well as my ipad 4 or ipad Air. The Wi-Fi signal from my modem does not seem to reach my iphone as well as my ipads. When i shake the phone slightly i keep hearing a strange sound as if something is loose in the back of the phone. Is this supposed to be so and how well is the Wi-Fi supposed to be on the iPhone 4s? I had a cheap blackberry before and even that had better Wi-Fi than my iphone. Is this a problem? I can walk aproximately 10 to 15 metres from the modem before my signal is lost but with my ipad i can walk to the end of the house and still have Wi-Fi!

Its seems like your phone's Wi-Fi antenna or EMI shiled is lose. You can check this by just opening two screws in the bottom so that back glass can be taken apart then to make sure if there isn't anything broken or lose screw inside.

  • Why do I do this? I'm very very very tired yet I don't want to sleep? I want to sleep because I'm practically blinking and bobbing my head side to side like a drunken man but I just don't want to sleep. I watch tv or go on Facebook or play on my iPhone. And I'm starting to get dark circles. And as a guy I don't wear. Concealer or whatever
  • My iphone screen is very dark, but if I look very close, I see the apps slightly? My iphone screen is very dark but I still see the buttons slightly, but I have to look very closely in order to. It is definitely not the brightness, because the brightness is set to 100% and its way too dark anyway. I tried restoring my phone and turning it on and off, but nothing is working. Please help. What do I do? I literally threw it out of anger and its fixed.
  • My iphone 4s is charging very very slowly? I let my phone charge for about three hourse and it only charged from 3% to 5% and its really really slow; i'm not sure if its the battery or not. Also; i had finally charged it to 10% and i took it off the plug for a second the. It went back to 1%.
  • Laptop Wi-Fi signal very poor? I get Wi-Fi in most places around the house on my iphone and iPad but on my laptop the Wi-Fi stopped working so I had to connect it to hub with lead to get any internet, when I got it working again I could only get Wi-Fi on my laptop if I was in the room with the hub or directly in the room above, any ideas on why my laptop won't pick up signal anywhere?