You can sideload apps to your Fire TV. Not sure about Toggle and TVB Anywhere+ though.
Mi Box S has Android TV OS Google Play Store, a curated version of Google Play Store for TV. You can also aide load apps not available in its Play Store..
TVB Anywhere+ TV version is available from the store, but you need to pay for the SVOD subscription in order to use it.
SingTel TV Go and SingTel Cast are also available.
Toggle is not available and can not be side-loaded. Same for Starhub Go. But both Toggle and Starhub Go support Chromecast, so you can cast from your mobile phone since Mi Box S has built-in Chromecast function.
I get it now, so toggle and some apps are on the main google play store but unavailable on the google tv platform. Really appreciate the clarification.
Yes most apps can be sideloaded on fire tv but in reality some work well and some don't. While for those that work, chances are the app interface won't function properly and you can't navigate or click on the menu options. There is the option of getting a 3rd party fire remote but again that is a hit and miss with no guarantee that it will work on the app that you specifically purchase it for.