4 Mbps (on your iPad) is rather slow and might not be sufficient for what you want to do. What are the results on your PC (you say it's slower).
See if you can find (and pay for!) an Internet connection with s speed of 25 Mbps. Where I live (The Netherlands) such a subscription costs about 30 euro (33 USD) a month, including a landline for a phone. A slower connection than 20 Mbps isn't offered.
I assume all is fine if you take your devices with you to a friend that has such a faster connection; then it's nothing fatal on your devices, just a too slow connection with your ISP. For such a connection: you get what you pay for (faster = more expensive); if it's much slower: complain.
There is a lot of things I'd like to put down here so let's go:
- Speedtest results for today http://www.speedtest.net/my-result/i/2208738264
(For reference)
- Steam downloads has never exceeded 1MB/s in download speeds, and a game can take days to download.
- YouTube, when it isn't playing a video in 144p, will continue to load forever as does BBC iPlayer and most other social media outlets. It takes a good ten minutes for it to finally tell me that my connection timed out etc.
- I recently rented a movie from the iTunes Store but haven't been able to watch it because after about 2mins of downloading it will mysteriously stop and it has done that ever time I've tried.
- Whilst the internet is still diabolic on my iPad, it is still much better than on my PC. There is a clear difference in the download and upload speeds from device to device in my house.
- Some days the internet is completely broken all day, and other days the internet can suffice.
- Playing online games has become next to impossible because of timeouts, ping issues and rubber banding.
I have tried troubleshooting this over and over, reaching a dead end or a thread which has never been resolved. Do I need a new internet? Can I fix the one I have?

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