Once you have funded your account, either tap or swipe right on an asset on the home page. You can then tap "Buy" on the tile and enter the amount you'd like to purchase. Simply review your order details and swipe to confirm your order.
Tapping the "Pay with" section in either the amount input or confirmation screen lets you choose from different currencies, as well as payment cards.
Once your purchase has been processed, tapping the displayed balance leads you to the transaction history page.