This app was mentioned in 12 comments, with an average of 1.75 upvotes
I had the same problem with my Nexus 5. I found out the problem was IPv6. For some reason it just can't handle IPv6 over wifi. I was able to get back to normal speeds by using an app to switch back to IPv4.
If you're interested, this is what I used: https://play.google.com/store/apps/details?id=de.lennartschoch.disableipv6
You'll have to be rooted to disable IPv6. Once you're rooted, you can use the method described here: https://www.reddit.com/r/Android/comments/2z1gyo/fix_lollipop_wifi_issues_and_coincidentally_the/ However, on my phone SManager would occasionally freak out and cause my phone to lag pretty badly, so I just use this app whenever I need to turn IPv6 off (which you have to do every time you connect to a troublesome WiFi network): https://play.google.com/store/apps/details?id=de.lennartschoch.disableipv6 Note that you don't have to disable IPv6 on every WiFi connection, just certain ones. For example, my home and work networks are just fine, but the wireless at my in-laws' doesn't play nicely.
Disable IPV6 - https://play.google.com/store/apps/details?id=de.lennartschoch.disableipv6
The caveat is that sometimes it will switch back when you hop on a new network, but it's as simple as opening the app again and changing it back.
It's a bug in Lollipop. Notifications won't display while on wifi. It's seriously broken. You should either roll back to KitKat or root and disable IPv6 using this app.
Tl;dr : Usually, this is a problem with ipv6 on Android 5.x. This app can disable it but only with root.
I found a fix for my phone (Galaxy S4). I downloaded an app that disabled ipv6 on my home network and now gfycat and other apps work like a charm:
https://play.google.com/store/apps/details?id=de.lennartschoch.disableipv6
Interesting. You might want to try these steps to root then install the IPv6 disable app.
I recommend this app: https://play.google.com/store/apps/details?id=de.lennartschoch.disableipv6&hl=en
Works well - you'll have to check on it periodically to make sure it's still disabling IPv6, but otherwise it works well. You'll need root, but the one-click root on XDA is super easy.
Found an app that simply disables it with a switch: https://play.google.com/store/apps/details?id=de.lennartschoch.disableipv6
Would this be helpful? https://play.google.com/store/apps/details?id=de.lennartschoch.disableipv6