I don't need DVR service but I would like the ability to stream live TV outside of my home. I have the HD Homerun Flex 4K device. If I purchase this Android app for $24.99 does it allow out of home streaming or would I need to subscribe to the monthly DVR service?
No that app only works at home. The ability to stream while away from home requires Channels DVR Server and is only available with it and its service.