Thank you for your feedback. From the error message I can see that the URL prefix is an empty string. I can reproduce this error if I tap "Sync" button before I tap "Scan" button.
In order for "Sync" button to work you have to use "Scan" button at least once. We designed the workflow as follows:
- Build the app for NativeScript Companion App (see screen1.png)
- After the build completes you should be able to see QR code (see screen2.png)
- Use "Scan" button from the Notification Center (see screenshot1.png)
- Scan the QR code (see screenshot2.png)
After you successfully scan the QR code your app will be synced. Behind the scenes NativeScript companion app will save the URL encoded in the QR code. The initial scan is required in order to obtain the sync URL. Once you have used "Scan" button you don't need to use it further. Anytime you want to sync your app just make sure that you have saved your source code files and tap "Sync" button (no build is required).
I am sorry we didn't make the documentation more explicit about the workflow. Please let me know if the proposed steps work for you.
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