Home Projects Blog About Schedule a call DE

Mobile Wallet App for NFC Payments

From early prototype to initial public release — building the iOS wallet client and the analytics instrumentation that shaped every product decision along the way.

Role
iOS Engineer / Analytics Lead
Duration
10 months
Stack
Swift · iOS · Amplitude · Braze · BigQuery
Year
2022
Mobile Wallet App for NFC Payments

The Challenge

The founding team had a strong payments-infrastructure backend but no mobile expertise. They needed an iOS engineer who could own the client from blank canvas to App Store, with robust analytics baked in from day one — not retrofitted after launch.

Approach and Execution

I built the Swift client in parallel with analytics schema design. Every user interaction — from wallet balance view to NFC tap confirmation — was instrumented as a structured event from the start. A/B testing via Amplitude Experiments informed UX changes before they shipped. Post-launch, funnel analysis identified two key drop-off points that drove the v1.1 roadmap.

Results

100%
Feature coverage instrumented from v1.0
2.4×
Checkout conversion improvement after funnel analysis
4.6★
App Store rating at 6-month mark

Key Insight

Starting analytics schema design before writing UI code is the highest-leverage investment in a new product. The team could answer ‘why did conversion drop last Tuesday?’ on day 30. Most early-stage products can’t answer that question on day 300.

Outcome

The app reached 10K downloads in 90 days. The instrumentation-first approach meant the product team had clean data for every investor update and could run experiments without waiting for an analytics backfill.

Tech Stack

Swift · iOS · Amplitude · Braze · BigQuery

iOSSwiftNFCAmplitudeBrazeBigQueryA/B TestingFunnel Analytics

Got a similar challenge?

30-minute call · No prep needed · Clear gaps identified

Start the conversation →