Bits Credit Card

Overview

Bits is a UK fintech app that helps people build credit and get a credit card. It pairs a real card with a credit score simulator, rent reporting, an AI assistant, and a mascot that guides users through building credit.

My role

I built new features and fixed bugs across the existing iOS app, and led several of them for Android too. I prototyped product ideas for management, created the mascot and its animations, assisted the senior iOS engineer on the Apple Wallet integration, made data-driven changes to onboarding to lift conversion, and built an automatic monthly raffle that rotates through a yearly schedule with a master switch marketing controls from the CMS.

Hardest part

Making a credit-building app less boring and increase engagement. My solution was a mascot that reacts to your progress, and motivates you. I built a messaging system that ranks every candidate message by priority against the user’s current state, so the mascot surfaces the one thing worth saying instead of spamming generic messages. The same events drive an animation state machine, idle loops, reactions, and the transitions between moods, and the mascot is draggable, so users park it wherever they like on screen and it settles back into its idle behaviour from there.

Architecture & stack

Swift with UIKit and SwiftUI, MVVM-C using XCoordinator for navigation, SnapKit for programmatic layout. PassKit for Apple Pay and Wallet provisioning, Stripe for payments, Plaid for bank connections, SumSub for KYC and 3DS for payment authentication.

Contentful drives feature flags and remote content, so switches like the raffle ship without a release. Firebase, Sentry, Mixpanel, Intercom and Branch for analytics and support, IOSSecuritySuite for jailbreak detection, a WidgetKit home screen widget, XCTest with Quick and Nimble for tests, and Fastlane with Xcode Cloud for CI.

Achievements

• 5-7k monthly unique iOS-only downloads
• $500k MRR