Before sending funds: ensure you have the recipient's account code. This can either be a QR code or the actual Account Code which they can provide to you by tapping on their Account Info in the black box at the top of the Account Details screen and tapping one of the buttons next to "Account Code" under Other Details.
From your "Account Details" page tap on the "Move Funds Out" button and then select "Intrabank Transfer" and fill out the required info as seen below.
*If provided a QR code for your recipient then tap on the QR code icon in the Account Code section to bring up the camera to scan.
Verify the information is correct and then tap on "Transfer" at the bottom of the screen to complete the Intrabank transfer.