08 / Freelance
Pennywise
A personal-finance mobile app for tracking spending, budgets and goals, plus the marketing site that collected its waitlist.
- Company
- Freelance
- Role
- Mobile & frontend engineer, sole developer
- Period
- Jan 2024 – May 2025Live
- Links
- Visit site
- Stack
- ExpoReact NativeExpo RouterNativeWindRedux ToolkitMMKVSkiaNext.js
Pennywise
Personal finance app and website
Screenshots coming soon
What I built
- 01Onboarding, sign-up, verification and a multi-step password reset
- 02Wallets and budgets with charts drawn in Skia
- 03Bank account linking and secure local storage
- 04EAS build channels for staging and preview
- 05A landing site with waitlist, pricing, community and blog pages
Key decisions
- 01
Fast local storage
MMKV keeps settings and session data on the device, so the app opens straight into the right state.
- 02
From a component library to Tailwind
The second version of the site dropped the component library for Tailwind, which made theming and later changes much simpler.
01
The problem
People wanted to see where their money goes and stick to budgets from their phone, and the product needed a site to explain itself and collect sign-ups before launch.
02
The process
I built the app with Expo and Expo Router: onboarding, sign-up with verification, password reset, wallets, budgets and charts, with bank account linking through a third-party widget. The website started on the Pages Router with Mantine and was later rebuilt on the App Router with Tailwind.
03
The outcome
The website is live at iampennywise.com, and the app ships through separate staging and preview build channels.
04
What I learned
Android builds and network configuration take real time. Budget for platform work alongside feature work.