What are Smart TVs?They are basically TVs that has Internet access and can provide online contents like videos through web browsing or applications like YouTube etc.
Every manufacturer has their own offering but more and more are getting on a open platform and the following are the 3 main platform now.
This open source platform is currently being used by LG to replace their NetCast propriety platform. LG first used webOS version 1.3 and has now moved on to version 2.0 which is a marked improvement in terms of speed and features.
Currently being used by Panasonic to replace their Viera Cast / Connect platforms.
Firefox OS can do more than just TV. It is a platform that is suitable for any screened devices
A successor (though not that successful) to Google TV. Currently being used by Philips, Sharp and Sony and is based on Android 5.0 Lollipop but with a customised UI.
Don't be confused with those Android smart boxes that comes with pretty standard Android OS UI.
Note: Toshiba has a range that comes with Android. However, those are based on Google TV, a predecessor to Android TV