> For the complete documentation index, see [llms.txt](https://superfluid.gitbook.io/superfluid/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://superfluid.gitbook.io/superfluid/protocol-overview/in-depth-overview/super-apps.md).

# Super Apps

## Definition

Super Apps are smart contracts that are registered with the Superfluid Protocol allowing them to **react to Super Agreements**. Through callbacks, a Super App can "react" to the creating, updating, and deleting of Super Agreements that it's been engaged with by means of customized logic set in its smart contract code.

## **Reacting to Super Agreements**

**Callbacks** are what make Super Apps reactive. They are custom code that a developer can implement in a Super App that triggers when a Super Agreement to the Super App is created, updated, or deleted. This code could enact anything from minting an NFT to initiating a new CFA. 

### **Example - Stream Consolidator Super App**

A Super App, programmed to take all inbound flows to it and aggregate them into a single outbound flow to the designated Account Z, is deployed. 

**1.** Account A starts a CFA to the Super App of 100 USDCx/mo. *In reaction*, the Super App initiates an outbound CFA of 100 USDCx/mo. from itself to Account Z.

**2.** Account B starts a CFA to the Super App of 25 USDCx/mo and Account A updates its CFA to 50 USDCx/mo. The Super App reacts with the necessary flow update in its outbound CFA.

**3.** The Super App will continue to react appropriately as new accounts create, update, and delete CFAs to the Super App. 

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**NOTE**: While any smart contract can engage Super Agreements, a smart contract **must have callbacks defined** in order to be classified as a Super App.
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## Registering With The Protocol

What does it mean that a Super App must be "registered"? Upon deployment, code should be implemented in a Super App that identifies that the smart contract being deployed is in fact a Super App within the protocol. 

Why's this needed? Basically, if a stream is started to an address, the Superfluid Protocol will check if the address is in its mapping of Super Apps. If the address is identified as a Super App, the Protocol will look to activate the Super App's callbacks. This is what makes Super Apps reactive!

<figure><img src="/files/QciKxNUvmosOjMpVnBF6" alt=""><figcaption></figcaption></figure>

## Why Are Super Apps Needed?

Since Super Apps can react to Super Agreements, they create an intermediate layer of programmability to Super Agreement's that wouldn't be possible with just wallet-to-wallet action.

As a result, applications can be made that mesh together custom logic with Super Agreements actions to create scalable dApps with innovative user experiences.

For instance, you could create a lending Super App where loan repayment is be done via CFA stream rather than manual and repetitive repayment transactions. Also, imagine a Super App supporting on-chain subscriptions paid through CFA streams with a built-in affiliate program that automatically redirects portions of subscription streams to referrers. The possibilities with Super Apps are endless!

For more inspiration, check out these Super App examples below :point\_down:

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[Broken mention](broken://pages/-MUQ7Rhh4AWOpizAXhah)
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