iliad.
The app two million people opened in its first year. I’m one of the engineers who build it, on the iOS side.
iOS Engineer · July 2024 – now · iOS and Android, built native
What people see
Every line in one place.
Each SIM gets its own name and illustration, so you can tell them apart at a glance.
Device mock · My SIMs
One gauge for everything.
Your plan and your roaming in a single reading, and roaming is spent first.
Device mock · Consumption
Pick a country.
See what your plan covers there, before you go.
Device mock · Roaming by country
What’s underneath
The parts that never make it into a screenshot.
On the surface
- iOS app
- Native, for iPhone
- Android app
- Native, for Android phones
Underneath
- One design system
- A Figma kit with variants and variables, ready before development began
- One team
- 1 designer, 6 engineers, 1 product manager
Where it comes from
- The accounts people already had
- Same user ID, same password
- iliad’s own systems
- Plans, usage, roaming
Three decisions
Keep the keys people already have.
Customers already had a user ID and a password. We kept them, instead of inventing a new way in. Switching lines logs you out at the system level and keeps your credentials safely stored, so coming back takes a tap, not a reset.
Better than the website, not a copy of it.
The website already did most of this. The app only made sense if it felt like it belonged on a phone: native from the first wireframe, with the things you check most a thumb away.
Eighteen to sixty.
The people opening it range from students to their grandparents, with very different patience for technology. So: type you can read without squinting, buttons you can’t miss, and words nobody has to look up.
Where it surfaced.
#1Free app in ItalyApp Store and Google Play, February 2025
2M+People in the first yearAcross iOS and Android
4.5Average ratingOut of five
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