1) Amazon Fire: Great device if you’re already a heavy Amazon user. This has to have a Prime subscription- which is just like Netflix. Better actually since you can rent new movies (like iTunes). It’s fast and has lots of channels like HBO and Netflix. Amazon even has Starz as an add-on to their Prime videos. Rumored that Amazon will merge this with Alexa to create the ultimate home gadget. So stay tuned.
2) Chromecast- Google’s sharing device that lets you ‘cast’ anything from your phone or tablet onto the TV. In a way it’s more flexible since you use a mobile device’s apps to watch Netflix or any movie your phone has access to. But kind of cumbersome. Definitely not a turn-on-and-watch device.
3) AppleTV- if you’re deep in Apple products, this is for you. If not, I’d go with Roku. AppleTV has relied heavily on iTunes which I’m not a big fan of. But if you’re already in that space… knock yourself out.
4) My Favorite: Roku- this device has all the channels built in- unlike Apple. All the premiums (HBO, Showtime etc) which has a la carte subscriptions. The Roku app let’s you turn your mobile device into a remote. Great for typing in passwords since you can use the phone’s keyboard. It also is the only (or perhaps best) third party device that has an Amazon app. Giving you access to Prime movies and shows.