ngrok lets you put your localhost onto a temporary server and is very simple to set up. I've provided some steps here that can be found in the link:
- Download the ngrok zip from the link above
- Open the zip
- Run your server locally and take note of the port number
- In the terminal, go to the folder where ngrok lives and type
ngrok http [port number]
You'll see a little dashboard in your terminal with an address pointing to your localhost. Point your app to that address and build to your device.