To place a stock order using the E*trade mobile app, there is an 8 step process: 1) select the E*trade app, 2) sign into your account, 3) review your account assets, 4) select "trade" from the accounts page, 5) input the stock name, 6) choose order details like type and quantity, 7) preview the order, and 8) place the order by selecting the "place order" icon which purchases the shares.