Just signed up and downloaded the Android app. I saw this in your EULA:<p><i>When buying or selling bitcoin, you are buying or selling from Coinbase directly. Coinbase does not act as an intermediary or marketplace between other buyers and sellers of bitcoin.</i><p>What's the effective exchange rate for customers? You already say you take 1% of each transaction; is the exchange rate tied to the current trading price of one of the major exchanges, or are you setting that yourself (like retailers do for foreign currency)?<p>I imagine you're doing some of your own arbitrage, here. That's fine as long as prices keep going up. What happens if prices crash and a bunch of people put in buy orders? I assume this is where the 48hr window you give yourself to "retrieve offline funds" comes in. In that event, what price do your customers pay? The market rate when they put in the buy order, or the rate 48 hrs later when you deliver the bitcoins?<p>It's an intriguing and exciting service, but I fear you're either leaving yourself open to massive liability, or are going to be forced to screw over your customers in the event of rapid swings in the value of BtC.