In this app you can find the route from Valka to Riga and from Riga to Skaistkalnė or Žagarė. Each stage of the route has accommodation, which you can see both on the map and by expanding the stage descriptions. Most stages have detailed descriptions to help you plan your day on the way.
I hope you find the app useful and that it contributes to a great experience on your journey! Buen camino :)