A global catalogue
More than 350,000 items in 170+ categories, organised by continent and country — coins and banknotes side by side.
Android app · Ionic & Firebase
Global
Global
Collector
A mobile app for coin and banknote collectors: a global catalogue of more than 350,000 items across 170+ categories, your own collection and watchlist, and alerts for new releases and auctions — in six languages.
/01 The problem
Collectors of coins and banknotes still keep their collections in notebooks, spreadsheets and browser bookmarks. Catalogues exist, but they are scattered by country and rarely fit in a pocket at a fair or an auction, which is exactly where the questions come up: do I already own this one, what was the mintage, is this price reasonable?
Global Collector puts the catalogue and the personal collection into one app. It was also a deliberate engineering experiment: I wanted to build a real, published product with Ionic as the cross-platform framework and Firebase as the whole data layer, and to find out where that combination holds up and where it does not.
/02 What it does
CATALOGUE
SORTING
MY ITEMS
ALERTS
UX
CONTENT
Sort the way collectors think
By release date, nominal value, mintage or score, so a series can be browsed the way it is actually collected.
Collection and watchlist
Track what you own and what you are hunting for, and keep the two apart while you are standing at a fair.
Notifications
New releases, auctions and market updates, so a limited series does not pass unnoticed.
Dark mode and six languages
English, Slovak, Czech, German, Polish and Spanish, with a dark theme for long browsing sessions.
Articles and insights
Short pieces on collecting trends that give the numbers in the catalogue some context.
/03 How it works
/01
One codebase
The app is built with Ionic, so a single Angular codebase produces the native Android build published on Google Play.
/02
Firebase as the backend
Catalogue data, user collections, authentication and notifications all live in Firebase — no server of my own to operate.
/03
A catalogue that keeps growing
Items are imported and curated in batches per country and series, which is how the database reached 350,000+ entries.
/04
Published and maintained
Released on Google Play in 2024 and updated since — the app is a long-running product, not a demo.
/04 Under the hood
FRAMEWORK
DATA
PLATFORM
WHY
Ionic
A cross-platform framework over Angular: one codebase, native build, fast iteration for a solo developer.
Firebase
Firestore for the catalogue and user data, plus authentication and push notifications.
Android
Published on Google Play as com.prompts.gca, currently focused on Android.
Learning in production
The real goal was to take an unfamiliar stack all the way to a published product — the strongest way to learn a framework is to have to maintain it.
350k+Catalogue items
170+Categories
6Languages
2024On Google Play since
/05 FAQ
Where can I download Global Collector?
On Google Play, under the package com.prompts.gca. The app currently targets Android.
What can I keep in the app?
Coins and banknotes: browse the global catalogue by continent and country, add items to your own collection, and keep a separate watchlist of pieces you are still looking for.
Which languages does it support?
Six: English, Slovak, Czech, German, Polish and Spanish.
How big is the catalogue?
More than 350,000 items across 170+ categories, and it keeps growing as new series are added.
Why Ionic and Firebase?
The app started as a way to try that exact combination on a real product. Ionic gives one codebase for a native build and Firebase removes the need to run a server, which suits a product built and maintained by one person.