Does the mobile app only work witIOS 13?

Hello, alanf6464-gmail-. 

Thank you for reaching out to the Community. Currently, the compatibility for iPhone requires iOS 13.0 or later in QuickBooks Self Employed.  

 Please check these articles for your reference: 

• QuickBooks Self Employed mobile app  
• QuickBooks access for mobile devices 

Keep me posted if you have other questions. I'm always here to help. Take care and stay safe!