How We Built Zaplert: Real-Time Crypto Alerts & Production Stack Decisions
How Walkonweb built Zaplert—a mobile crypto alert app with Binance market data, rule-based triggers, Expo/React Native clients, and push notifications.
Introduction & Product Vision
Zaplert started from a clear job: let traders set price and percentage rules on live crypto markets, then notify them on their phone when those rules hit—without forcing them to stare at charts all day.
Stack Selection: Expo, React Native, and a dedicated API
The mobile client is built with React Native and Expo so Android and iOS share one codebase for auth, markets, favorites, alert creation, and push token sync. A separate API evaluates alert rules and persists accounts, alert history, and delivery logs.
Live Market Data Without Overclaiming
Zaplert uses Binance spot market data (REST + WebSocket) for live prices and movers, with TradingView charts on coin detail for context. Alerts are rule-based—price above/below, percentage moves, ranges, and watchlist updates—not AI trading signals.
Key Takeaways for Software Founders
Shipping a real product forces honest scope: notifications, privacy pages, data deletion, and mobile packaging matter as much as the happy-path UI. That production feedback loop is what Walkonweb brings to client work.
Related Engineering Capabilities
Talk through your software project with us
We reply within 1 business day—every time. Early clients get closer founder collaboration and flexible pricing while we build out our portfolio.