When you open Cashinator with a stable internet connection, the app will update all conversion rates in the background. This only happens every 12 hours at most, so that data is not transferred unnecessarily. In addition, the query is limited to the worldwide exchange rates that convert the amount into euros. As soon as you enter a new expense in a foreign currency, the last known rate is stored in the expense together with the amount. If you use a different home currency than the euro, an additional exchange rate will be saved, which allows the euro to be converted into your home currency in the next calculation step. Thus, the amounts of expenses are in sync with all other participants on all devices. Amounts also do not change along with another update of rates the next day.
Should another participant prefer a completely different home currency than that of the others, the last rate known to the device in that home currency will be used to calculate the result. That should be a very rare case but could lead to a slight inaccuracy when looking at the balance sheet on different days.
The advantage of this method is that instead of around 29,000 possible courses, only 170 have to be transferred. This reduces the amount of data so much that the app still performs very well abroad and there are no high mobile phone charges.