I need to send 4+ photos attached to invoices on the mobile app but can only send one photo. Why is this? is there a limit to how many photos/size of attachments?

Hello there, @liz-bayley.

Welcome to the Community. You can only add one attachment to your invoice using the QuickBooks Mobile app. 

To attach multiple attachments, you can add them to the Notes & Attachments instead. Here's how: 

1. Go to Notes & Attachments, then click the Plus Icon.
2. Choose a customer/vendor to assign the attachments in the Assign To field.
3. Click the Pin icon to browse files, then click on Save. 

See screenshots below: 

For additional insights, check out this link: Attachments in QuickBooks Online. It helps you learn about the acceptable file types for attachments and the transaction types that can keep them. 

I'm also adding articles that you can use in the future. It'll guide you in adding notes to transactions using your mobile apps: 

• Add a note to a transaction in the QuickBooks Online app (iOS only)
• Add notes and photos using the QuickBooks Online app (Android only)

Feel free to get back here should you have additional concerns. We're always delighted to help.