Yes, you can place a buy or sell order with full wallet balance in one go. This can be done via "Buy Max" or "Sell Max" option while you place your trade order.
Using this option, your complete balance of cryptocurrency in Zebpay wallet will be added to your buy or sell order.
1. Tap on "trade" from home screen. Either from buy or sell, click on "buy max" or "sell max" respectively. This will add your complete cryptocurrency balance in the amount. You can now proceed to place buy or sell order to trade with full balance in one go.