# Call-to-action text support

> Customize call-to-action (CTA) text in Unity Exchange ads to improve user engagement and align with campaign goals.

> **Note:**
>
> Call-to-action text support is only available for iOS apps.

Call-to-action (CTA) text support enables customization of CTA buttons with options like **Shop Now** or **Learn More**, broadening their usability.

## Bid Response

Unity supports **Install Now** for app-related ads and **Learn More** for non-app-related ads as default text options for the Call-to-Action button. Unity provides DSPs the option to change the default text to better suit the creative. Additionally, Unity also supports **Shop Now** as an ad text option.

| Status     | Bid Response                                                        |
| ---------- | ------------------------------------------------------------------- |
| To disable | Don't add the extension to your bid response                        |
| To enable  | Add the `resp.seatbid[0].bid[0].ext.cta_Text: "Shop Now"` extension |

Unity implements a verification logic to only display supported Call-to-Action text. If unsupported ad text is received, Unity will display the default text **Install Now** or **Learn More** in the Call-to-action button.