Ride Booking Application

On-Demand Ride Booking & Mobile Payment

The Challenges

An application was already live and serving customers. It had to be replaced completely, with nothing the existing users relied on left behind.
Android and iOS were maintained separately, so every change cost twice and the two versions drifted apart.
Korean customers pay with Toss, Kakao Pay and Naver Pay. A platform that did not accept them would lose the sale at checkout.
Registering a card meant typing sixteen digits, an expiry date and a security code on a phone. Many people give up at that screen.
There was no way to verify who a user actually was before money was attached to their account.
Marketing had no promotion tool. Discounts could not be issued, tracked or withdrawn without a developer.
Customers could only book for right now. They could not reserve ahead, look at what they had booked before, rate the service, or dispute a charge.
Pricing depended on someone assessing the job. That does not scale, and two people assess the same job differently.
Drivers and customers both needed to see the state of a booking change as it happened, not on a refresh.

Started by taking the original application apart and documenting what it did, so the migration was measured against the real product rather than the documentation of it.
Rebuilt the whole application in Flutter, covering Android and iOS from one build. Feature parity first, new work second.
Put identity verification in front of payment. NICE Service confirms the user is who they say they are before a wallet can be attached to the account.
Integrated the wallets Korean customers already have - Toss, Kakao Pay, Naver Pay - plus KICC, so payment is a familiar step instead of a new one.
Added OCR card scanning. The customer photographs the card and the fields fill themselves.
Built an admin page for coupons and points, so the business runs its own promotions and can see what is being redeemed.
Released coupons and points on the customer side, applied as a discount at the moment of booking a car.
Added booking reservation, so demand can be placed in advance rather than only on the spot.
Added booking history with star ratings and a payment claim path, giving the customer a record and the operator evidence.
Integrated an AI detection model that reads the case and estimates the price on its own.
Used Google Maps SDK for location, routing and the map screens.
Ran real-time updates over WebSockets and put iOS builds through TestFlight for continuous beta testing.

Customers pay with the wallet already on their phone, so the payment step stops being a reason to abandon a booking.
Adding a card is a photo instead of a form, which removes the most common drop-off point in sign-up.
Every paying account is tied to a verified identity, cutting off fraudulent accounts and giving the operator a footing in payment disputes.
Marketing runs its own campaigns. Coupons and points go out, get monitored, and get pulled back without an engineering request or a release.
Advance reservations let the operator see demand before it arrives and plan drivers against it, instead of reacting on the day.
Star ratings turn service quality into something the operator can actually measure per booking, and the claim flow gives customers a route to resolution that does not go through a call centre.
Pricing is consistent because it no longer depends on who assessed the job.
iOS and Android customers get the same features on the same day, so neither half of the market waits.

Mobile: Flutter (Dart), cross-platform for Android and iOS
Backend: .NET framework - server-side processing, business logic, API management
Networking: RESTful APIs for third-party integration; WebSockets for real-time bidirectional communication
AI: detection model for automatic case analysis and dynamic price calculation
Maps: Google Maps SDK - location tracking, routing, map features
Payments: Toss, Kakao Pay, Naver Pay, KICC
Identity: NICE Service
App services & distribution: Firebase; TestFlight for iOS beta distribution

Flutter.NETREST APIsWebSocketsGoogle Maps SDKFirebaseTestFlightNICE Service