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mycelium-com / wallet-android

Mycelium Bitcoin Wallet for Android
http://mycelium.com
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Rate fiat problem MyCelium API server #564

Closed Array-0 closed 3 years ago

Array-0 commented 4 years ago

Mycelium WAPI Server seems always is returning modified values compared with real source. I attach screenshot example. Its not a delay, price shows always lower in all source providers. https://imgur.com/a/oI0qLtP

Array-0 commented 4 years ago

Is not a problem of client. The rates come from https://mws30.mycelium.com/wapitestnet/wapi/getExchangeRates API json

Giszmo commented 3 years ago

"The exchange rate" is not actually a thing. Exchanges report:

We often use the average of the best buy and best sell price while other sources might present the last trade or even the moving average. At times those can diverge.

As for your screenshots, in the case of Kraken, we use this API call.

That reply is a bit cryptic. Our code uses the first child from the "c" value which according to the api documentation is the last trade's price. That looks good to me.

Array-0 commented 3 years ago

Hello, I investigated a bit and the exchange rate only is good in USD. When you choose EUR and Kraken fiat rate exchange for example. It checks XBTUSD and after do a EURUSD conversion on other place. The correct way is check XBTEUR on Kraken directly.

This cause me a lot discusions with other people who use mycelium too about the real amount when I receive/send.

I attach screenshot. Real XBTEUR in Kraken and mycelium rate. https://i.imgur.com/LCtEn1c.png

Giszmo commented 3 years ago

Your observation is correct. If that is unacceptable, I suggest to open a new issue suggesting/requesting a feature that makes sure that exchange rates are not computed the way they currently are.