What's the difference between a cheap router and a good router?

Just wanted to know the difference between a cheap router and an expensive router, I know that is a very broad question, I'm just a bit confused on how a router works. Does it increase my Internet speed on multiple devices? I get 50Mb per second, Well at least that's what I pay for. I have a PS3 two iPhones and a tablet, as well as a desktop PC that is wireless. Can anyone recommend an excellent router under $150

The price difference is usually due to functionality of the router, and the types of services it provides. In general, routers will not increase or decrease network speeds (unless there's a hardware or software malfunction). Most routers use gigabit interfaces now and it's unlikely you'll have an Gb connection to the Internet, so your Internet connection will be slower than the maximum speed of the router interface.

For home use most any Cisco/Linksys or Netgear router will do.