Yes. If you have enough money in your wallet, you can purchase a new asset outright. If you only have a portion of the money in your wallet, you can pay for your asset with the money in your wallet and do an ETF or once-off debit order to pay for the balance.
In time, you will be able to use the app to move the money into more traditional investment products offered by Fedgroup, such as the Money Markets or Unit Trusts. This would further enhance your returns and, as existing clients, there will be no minimum investment.