> For the complete documentation index, see [llms.txt](https://docs.questera.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.questera.ai/questera-ai-sdks/flutter-sdk-components/expansion.md).

# Expansion

- [Referral Component](https://docs.questera.ai/questera-ai-sdks/flutter-sdk-components/expansion/referral-component.md): The Referral components are  reusable flutter component designed to facilitate user referrals and rewards. It allows users to earn rewards by sharing a referral code with friends
- [Cross-Selling Component](https://docs.questera.ai/questera-ai-sdks/flutter-sdk-components/expansion/cross-selling-component.md): Boost revenue and enhance user satisfaction with our automated upselling. Tailored suggestions for additional services or products are seamlessly offered based on individual product usage, optimizing