Zapp is a privacy-first mobile wallet that lets people pay with Zcash (ZEC) while recipients receive local fiat into familiar payment apps like UPI, Alipay, or PIX. Users can make cross-border payments and everyday purchases without exposing who they are paying, how much they are sending, or which assets they hold. The app streamlines complex cross-chain DeFi flows by using NEAR Intents and RHEA Finance under the hood, so earning yield on idle ZEC feels like a simple deposit and withdraw experience. It improves safety by keeping funds in a self-custody wallet with biometric authentication and by avoiding centralized exchanges or custodial ramps for ZEC↔fiat conversion. Facilitators use the linked web dashboard to manage orders and payment rails, earning spread while giving users a fast off-ramp that still preserves on-chain privacy.