For every area Roku enters, it has to deal with all of the country's rules and regulations. The processes in each country is different, and many have multiple agencies that must be navigated.
None of this is done until Roku (or any outside company) does research into the market to determine what level of sales is expected, how much it will cost to enter the market, and the return on investment.
Roku won't announce entry into any market until that is done. Roku will also not announce a decision to not enter a market.
Roku is officially unsupported in the Philippines. If you bought in-country, it was from someone who is doesn not have an agreement to sell in country from Roku. You would have to import the device from a country in which Roku is sold, or purchase from someone who imported outside of Roku's supply chain.
It is not unexpected for them to not make a mobile app available in an area they don't support.
For now, your only option is the Voice Remote Pro, which is a standalone remote that includes headphones for private listening.
Roku Community Streaming Expert
Note: I am not a Roku employee.
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