iOS NEM Wallet CRASH

I have just installed the iOS NEM wallet.
These are the steps that I did, let me know if I did anything wrong.

at the ACCOUNTS page, I add account.
I select CREATE NEW.
Type the Account Name, in this case; I just use ‘wallet01’.
Click the ‘Create New Account’.
Warning message box appeared, asking to go to do back up private key by doing the ‘export account’.
Now back to ACCOUNTS page.
Click the ‘wallet01’, click the ‘more’ at the bottom right, then select ‘Export Account’.
Click the ‘Confirm’ button to use the application password.
And then I can see big QR code with two options to SAVE QR and SHARE QR.
Whenever I click on SAVE QR the app will crash and shut down.
What is this SAVE QR suppose to do? Saving the QR to where?

Please help thank you.

Saving QR code should save image probably on your storage.
I’m not aware of IOS but for Android it sometimes means that app don’t have permissions.
No matter what you should report this issue on github: https://github.com/NemProject/NEMiOSApp/issues

So what should I do to back up private key? Do a normal screenshot of my iPhone?

Screenshot should do the trick. As a test please do screenshot, display it on other device and try import into phone (Add account -> Scan QR)

the QR code is it for the public key or the private key? Or both?
The public key is hidden, I have to tap it for it to show, so should I take the screenshot with the private key shown?

QR code contains also private key but for import it you must provide password to decode. When you show private key is presented as plain text (without encryption).