Please see below steps on how you can go about getting a bank statement on the mobile app:
Log onto the app,
Tap on the tile that shows your account details and balance,
Under "Your documents", select "view" and choose between a 3 or 6 months statement as suitable to you.
The 3 dots on the right hand side will give you an option to either download the document or send it as mail. Should you choose 'download', the document will be saved on your device. Should you choose 'send as mail', you will need to input your email address and the document will be sent to you.