How to Modify or Cancel Orders on MT4 (Android) Trading Screen
When you tap "Trade" in the bottom menu, your open positions and pending orders (new limit and stop orders) will be displayed.
From here, you can modify or cancel pending orders.
How to Modify Pending Orders from the Trade Screen
Tap the order you want to modify in the "Trade" screen.
Select "Modify Order" from the displayed menu.
Enter the changes (levels for Stop Loss or Take Profit) on the order screen and tap "Modify" to update the order.
How to Cancel Pending Orders from the Trade Screen
Tap the order you want to cancel in the "Trade" screen, select "Delete Order" from the displayed menu, and tap "Delete" on the confirmation screen to cancel the order.