There's a low end Android TV box on Ali Express for $26 and that was after about a minute of looking. I've had Android in my Shield for 4 years and it's been great. Keeping it maintained is up to the device manufacturer though, so I wouldn't expect that kind of reliability for $26. The market isn't there yet, so Roku has an advantage, but there's a reason why I turned down a job with them last year. There's a limited time where they will be viable. They're competing against some of the biggest companies on the planet. I have friends there and wish them luck, but I wouldn't go long on their stock.
Apple is never going to make a $30 streaming device to compete with Roku for a stand-alone device. They are now happy to have the AppleTV app on competitors and some TVs now support AirPlay.
Chromecast requires another device to actually use. That will never be good enough to be the only solution for smart TVs.
Amazon maybe. But they really don’t have a value proposition over Roku.
