Last updated: 31 October 2026

Support — Koinvert

Koinvert is Aumatex’s converter for iPhone: currencies, crypto and precious metals, with history, favourites under the result and a calculator in the amount field. 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 and, if that does not answer, from currency-api.pages.dev: the app makes a read-only request and sends nothing of yours.
  • The time of the last refresh is always at the foot of the converter: “Last updated: Today at …”, “Yesterday at …” or “On … at …”. Settings › Rates and data › Last updated shows the same.
  • To refresh, pull the converter down, or tap Settings › Rates and data › Update Rates. Freshly downloaded rates stay valid for an hour: within that time the app does not ask for them again.
  • 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, calculate, find again

  • Pick the assets in “From” and “To”, type the amount and the conversion is immediate; the two-arrow button between the currencies swaps the pair.
  • The amount field is a calculator too: with the keys above the keyboard (+, −, ×, ÷) type, say, 12×3+5 and the total appears under the field, and that is what Koinvert converts; = puts the total in the field, Done closes the keyboard.
  • Tap the result to copy it to the clipboard: “Text copied” confirms it.
  • When you close the keyboard the conversion goes into History, which keeps the 200 most recent: swipe an entry left to delete it, or tap Clear to erase them all.
  • 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.

Favourites and primary currency

  • In the currency list, tap the heart beside a currency to add it to Favorites: favourites sit at the top of the list, and Edit lets you drag them into your order. You can also manage them from Settings › Converter › Manage Favorites.
  • Settings › Primary currency sets your home currency: it comes first in the list, above the favourites.
  • Under the result, the “In your favorites” card shows the amount in your primary currency and your favourites, up to eight rows: tap one and it becomes the target currency. If you do not need it, turn off Settings › Converter › Favorites under the result.

Settings and appearance

  • Settings come in cards: Primary currency and Language at the top, then Converter, Rates and data and Appearance; further down More from Aumatex, Rate Koinvert and Share Koinvert, and last What’s New and About, which holds the website, support, the privacy policy and the credits.
  • Settings › Appearance holds the Theme (System, Light or Dark), the App icon out of eight (Midnight, Graphite, Emerald, Ocean, Black gold, Aurora, Ivory, Classic), the Accent color out of eight, from Gold to Emerald, and Haptic feedback. Icon and accent change at once, with no restart.
  • Settings › Converter › Smart decimals highlights the extra decimal digits; Unit of Measure picks Ounce (oz) or Grams (g) for precious metals.
  • Settings › Language shows Koinvert in any of its 11 languages, or follows the Device Language.

The other Aumatex apps

  • Settings › More from Aumatex lists the other Aumatex apps on sale in your country; those not out yet appear by themselves the day they are released, with no Koinvert update. Tap one and its App Store page opens over Koinvert.
  • Now and then, at the foot of the converter or of History, a tip about another Aumatex app appears, marked “From the makers of Koinvert”: never in the first week of use, one at a time, and once you open or close it at least a week passes before the next.
  • To dismiss it, tap the × at the top right of the card: an app closed or opened is never suggested again. There is no switch that turns the tips off altogether.
  • The system prompt asking for a rating appears only right after a conversion is saved, once you have used Koinvert for three days and have ten conversions, at most once per version and 60 days after the previous ask. Settings › Rate Koinvert opens the review form whenever you like.

Starting over

  • Settings › Rates and data › Clear Data, confirmed with Delete, erases history, favourites, settings and saved rates, and takes Koinvert back to the welcome screen.
  • The accent goes back to Gold too, and the tips about the other apps start from scratch, with a new quiet week; the app icon, though, stays the one you chose until you change it in Settings › Appearance.
  • 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: every icon and accent is for everyone, and 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.

Still stuck

Write to us with the problem, your device and your system version. We answer in English and Italian.

supporto@aumatex.it
Koinvert privacy policy