Last updated: 23 September 2026

Support — Koinvert

Koinvert is Aumatex’s converter for iPhone: currencies, crypto and precious metals, with history and favourites. It is free, has no account and no in-app purchases, and keeps working offline on the last saved rates.

Koinvert

Where the rates come from

Rates come from the public currency-api dataset, served through jsDelivr: the app makes a read-only request and sends nothing of yours.
The time of the last refresh is always on screen: “Today at …”, “Yesterday at …” or the exact date.
With no connection the app shows “Offline - showing cached rates” and keeps converting with the last rates it downloaded.
Rates are indicative and for information only: for a real transaction, the rate your bank or exchange applies is the one that counts.

Convert, save, find again

Pick the assets, type the amount and the conversion is immediate; swapping the pair is one tap.
Favourites keep the pairs you use most within reach; History keeps your recent conversions.
If you see “Pair not convertible with EUR-based rates”, that combination is missing a hop in the public data: convert in two steps instead, for example through EUR or USD.

Starting over

Settings › “Reset App” erases history, favourites and settings, and takes Koinvert back to the welcome screen.
It affects this device only and cannot be undone: there is no copy elsewhere, because Koinvert syncs nothing.

Cost and data

Koinvert is free, with no subscriptions: there is nothing to restore on a new device.
There is no sign-up, no login and no server of ours: history, favourites and settings stay on your phone.