A second currency, not a second app

The problem

The wallet held one currency, and everything about it was built on that assumption: one balance, one amount field, one set of rails. Adding euros meant every money surface suddenly had to answer “which currency is this?”, on mobile and desktop, when adding, withdrawing and converting. Euros were a strategic bet for Airtm: EURC, the euro stablecoin, opens a large market the dollar wallet did not serve, and demand was already coming from it.

Three things could not move. The rails differ by currency (euros leave over SEPA, dollars do not), so the flows could not be made identical. The naming was settled product-wide: users see USDC and EURC, never internal or legacy labels. And the second currency could not earn its own app: the same screens had to carry both, for people who would only ever hold one of them.

A currency switch on the balance: one control, two states, everything below it reacting. It demos well, and I built one to be sure. It puts a decision before the task, when the person already knows which money they are moving; it makes the two currencies compete for the same space; and it hides half of your money behind a control you have to notice.

Currency became a place, not a mode. Euros joined the carousel the home already had, with the same Add, Withdraw and Convert as dollars; the pill at the top became the total of every wallet, and a tap opens the sheet that lists each one in its own currency; every card opens the same wallet page, for dollars and for euros; and Convert puts the rate on screen before the amount. The tour above walks through each of them.

Comparison. The sheet lists the wallets; nothing on the home weighs one currency against the other, because that is not a question the product should pose during a transfer. Someone who wants to compare reads two rows. I took that trade deliberately: fewer people lost in the flow is worth more than a feature for the few who are optimising.

Shipped

The EURC card, the total and its sheet, the wallet pages and Convert are live in the Airtm app, as rebuilt above — checked in September 2026, and Airtm’s help center describes the euro balance.

Not shown yet

My designs for withdrawing euros and for recovering from a short balance went into build too, with engineering never blocked on design. They stay off this page until I can show how they shipped.

Numbers

Usage figures are Airtm’s to share.

I designed the pattern to take a next currency, not only this one: a card in the carousel, a line in the total’s sheet, a page of its own. Adding a wallet is now a matter of filling those three places. The app had no interaction patterns for holding more than one currency, so I had to write them, and they outlived the feature. Other teams reused the components and the patterns on their own surfaces. The work went through design reviews with the design team and a review with stakeholders before build.

The design was meant to move three signals, and they are the ones I would put on the dashboard before the next currency: whether people who receive euros find them without contacting support; whether euros get used and not only held, counted as conversions started from the EURC wallet; and whether a conversion that starts gets finished, measured between the amount and the confirmation. Airtm owns those figures, so this page states the signals, not the numbers.