AmanuCash Keyboard Extension

Demo

About

Why are you participating for Based LatAm? We are developing AmanuCash, a wallet built on Base that aims to make digital currency as simple and intuitive as cash. Our journey started in Argentina and we are committed to growing throughout LATAM. This region is at the core of our mission, which is why we’re excited to participate in Base LATAM. For this hackathon, we are focusing on developing an innovative feature—a keyboard extension that will revolutionize the payment experience by integrating seamless, everyday payments directly into any messaging apps. This feature has never been seen before in the payment space and we believe it will finally make digital payments super simple. Additional Features AmanuCash is already the only wallet that enables phone-to-phone contactless payments using ultrasound technology on any smartphone, creating a seamless experience similar to Apple Pay. However, what sets us apart is that you can perform these transactions with anyone, anywhere, all while maintaining self-custody of your assets. During the Buildathon, we added a new feature—AmanuKeyboard, which integrates our wallet directly into the keyboard. This extension allows users to send or request payments effortlessly from messaging apps, making crypto as intuitive as sending a text. This innovation brings us one step closer to making digital currency as simple as cash.

How it's made

What challenges are you focusing on? When sending a crypto payment to friends on a messaging app we often have to switch between apps, ask for the correct chain, currency, and public address, which makes the experience cumbersome and frustrating. We’re solving this by creating a keyboard extension for AmanuCash, allowing users to send payments directly from their keyboard without leaving the conversation. This simplifies the process, making crypto payments as easy and seamless as sending a message. How does your submission address this challenge? We’ve developed an extension for our wallet, AmanuCash, called the AmanuKeyboard, which adds a new section to the keyboard (like switching between languages or emojis). When users select AmanuCash, they are presented with a simple UI that allows them to quickly choose an amount to either send or request. When they press “Send,” the transaction is signed using a session key, with no need for the user to manage gas fees because AmanuCash sponsors them. The payment is shared as a link that safely holds the funds until the recipient claims them by clicking the link. If the user presses “Request,” a link is generated for the other party to easily pay into the user’s address. This project has the potential to simplify digital payments drastically, making crypto as easy to use as sending a message. By integrating directly into the keyboard, we’re eliminating the friction of switching between apps and handling complicated payment details, which will improve accessibility and adoption in LATAM, where fast and simple payment solutions are in high demand. Challenges we ran into AmanuCash is built as an Smart Account having as unique key "Passkeys" the big advantage is that the user as hardware level security like a ledger without having to manage seed phrases, the best of both worlds. Because Base is on Superchain it has the RIP-7212 making passkey wallets super cheap. The issue is that passkeys don't work on keyboard extension, we can't sign from the keyboard with biometrics. So we create a session key, hosted in an Amanu server that as the only permission to generate links. The advantages is that the admin user can revoke it whenever they want and if the key get hacked it cannot hack the wallet that easily because of the low permission on it. This solution as been usefull to provide this world premiere functionality of keyboard extension wallet for this hackathon, the time we figure out how to host the session key on the user device and sign and send manually the user, so it can benefits the best self-custodial experience, mixed with the best experience.