Refreshing prices
How prices update — daily with the catalog, or on demand for your whole collection.
Prices in Silvane are daily market aggregates that arrive with the card catalog's daily update — see Prices & Market. You don't normally have to do anything.
Update now
When you want fresher numbers than this morning's — say, mid-spike — go to Profile → Storage & Sync → Prices and tap to refresh: Silvane fetches current prices for every card in your collection (with a progress bar; it needs a connection).
Refreshed prices take precedence everywhere values are shown — binders, decks, portfolio — until the next daily catalog update replaces them with its own (by definition at-least-as-fresh) numbers. Nothing to undo or manage.
Silvane always shows market prices — there's no way to pin a custom price on a card. For what the numbers mean and where they come from, see Card prices.