My Roku remote long ago stopped working so I downloaded the app and been using that. Well my home internet has gone out and I’ve been trying to connect my tv to my hotspots. Neither will work. Every time I refresh the app it says it’s still buffering. I don’t know what to do
You can’t control your Roku with the app until the Roku is connected to the same network as the device with the app. That requires a real remote. A Roku TV can use a universal IR remote that supports Roku TVs, so you don’t need a brand specific remote.
Additionally, you cannot share the hotspot connection between the Roku device and the mobile app if using a single mobile device for the hotspot. (cannot operate both the device and the app on a single phone).
You will need one mobile device (ie. your phone) and connect the Roku device to that phone's mobile hotspot. You will then need another phone to run the mobile app in order to connect to the Roku device.
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An alternative method would be to use a laptop or computer as the mobile hotspot. Connect your Roku device to the laptop's mobile hotspot and then use your phone to run the mobile app and connect to the Roku device.
Depending on which Roku device you own (Settings/System/About), you may need to verify that your hotspot is using the 2.4ghz wireless band. (In Android, can select either band in hotspot settings. In Apple, may need to enable Maximize Compatibility under hotspot settings.)