# Is Dark

Reflects if it is dark outside. 

This is decided based on the time of the day. You may want to show a dark theme when it is dark to improve the user experience.

{% tabs %}
{% tab title="Typescript" %}

```typescript
const onIsDarkChange = (value: boolean, timestamp?: Date) => {
    console.log(value, timestamp);
};


COBI.app.isDark.read(onIsDarkChange); // Instantly get the current value
COBI.app.isDark.subscribe(onIsDarkChange);
COBI.app.isDark.unsubscribe(onIsDarkChange);
```

{% content-ref url="../../entities/placemark" %}
[placemark](https://sryvkver.gitbook.io/cobi.bike/entities/placemark)
{% endcontent-ref %}
{% endtab %}

{% tab title="Javascript" %}

```javascript
const onIsDarkChange = (value, timestamp) => {
    console.log(value, timestamp);
};


COBI.app.isDark.read(onIsDarkChange); // Instantly get the current value
COBI.app.isDark.subscribe(onIsDarkChange);
COBI.app.isDark.unsubscribe(onIsDarkChange);
```

{% endtab %}
{% endtabs %}