Chris

AFAIK you don’t actually load apps onto the Chromecast, it just acts as a receiver for whatever you ‘cast’ to it from your phone, tablet or computer. Unless they’ve changed that recently. I don’t know for certain.

With an Amazon Fire stick, basically you’re adding smart tv capability to you telly via a spare HDMI port. You load apps onto the fire stick (iPlayer, Netflix etc; although naturally Prime Video functionality is already integrated), sign in to the apps and away you go. The fire stick comes with its own remote control that is voice controllable, so while you can control the fire stick from an app on your phone, you don’t need to.

We bought ours in order to smarten up our living room tv. When we bought a new smart tv the fire stick went into the spare room. It’s a cost effective way of adding smart functionality to a cheap tv, or to a more expensive one whose manufacturer is useless at adding streaming app support ... again I can’t speak to how necessary that is, as our tv is a Samsung and they’re excellent at adding every new streaming app as it’s launched.