Can Roku be used on multiple tv sets is different rooms by purchasing additional player for 2nd tv?
We have a tv in the family room, and another tv in my granddaughters bedroom. It is possible to run a Roku player on both tv's if we purchase and additional player?
Yes, and you can have up to 10 devices on same Roku account to share subscriptions. RokuTV is a "device" for account purposes. Or maybe setup different account for some TVs and PIN lock the channel add function (limited parental control).
Sound across multiple devices unlikely to be synchronised, can be annoying if two devices in earshot playing same (live) stream.
Wireless remotes (sticks/voice remotes) can only be paired to one device at a time. App can pair to multiple.
IR remotes will control any device that can "see" the remote (line of sight or reflected off walls/ceilings). Which can be a bit annoying if TVs are close together. Only sticks are immune from this (all other devices support both IR and wireless)
A very few channels limit simultaneous streams per subscription or limit linked devices. NowTV in the UK has a device limit on standard subscription, I think I have seen HBOMax limits simultaneous streams in US (do your own research across your favourite subscriptions)