It's not enough to just add Analytics code for SPA sites, as it doesn't track client-side navigation. So we have to pass navigation events manually and this component does exactly this.
Install the component:
npm i sapper-google-analytics
And add it to your src/routes/_layout.svelte
:
<GoogleAnalytics {stores} id={ga_measurment_id}/>
<script>
import GoogleAnalytics from "sapper-google-analytics/GoogleAnalytics.svelte"
import { stores } from "@sapper/app"
let ga_measurment_id = "UA-SOMETHING" // your analytics id
</script>