Channel apps for Roku are created, provided and maintained by the channels themselves. Roku just provides the platform on which they are run.
There are two steps to a channel becoming available on Roku in any given geographical area.
The channel owners must authorize the distribution of their content in that region. In many cases, the channel must license the ability to distribute the programming into that area from the actual owners of the content, and some other licensees may already have exclusive rights in that region that can limit what can be shown. Disney has apparently done this for Singapore.
The channel owners must create a version of their channel app for the Roku that is configured to allow its use in that region and provide it to Roku for distribution. This is controlled by the channel providers, not by Roku. Each major streaming service (Roku, Amazon Fire, Google Chromecast, Apple TV, etc.) will have to have a compatible region-authorized version of the channel app created for it.
If a particular channel is available in your region via other devices but not on Roku, then it sounds like the channel has not yet released a Roku version that is enabled in your region. I would suggest you contact the channel about this directly, but don't be surprised if the front line people at the channel do not understand the problem is at their end.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well. If this post solves your problem please help others find this answer by clicking "Accept as Solution.".
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