Cant send estimate or invoice from tablet or phone

I've got you, Neil. Let's work together to perform some troubleshooting steps to resolve the error message you received while sending emails with estimates and invoices using your phone.

Beforehand, can I ask what's the exact error message? If you could provide a screenshot, it would be greatly appreciated.

To start with, if you're using an iOS device, you can follow these steps:

1. Go to Settings and click General.
2. Select iPhone Storage, then choose the QuickBooks Online app.
3. Hit Offload App.

For Android devices:

1. Go to Menu, then click More Options.
2. Select Settings, then tap Refresh Data.
3. Click YES to confirm.

Once everything's settled, you can then check if you're now able to send invoices and estimates. If the issue persists, you can uninstall and reinstall the app.

To learn which QuickBooks Online (QBO) mobile app features are supported, I've added this article: Compare mobile app features.

Alternatively, you can access your QuickBooks account via browser to send estimates and invoices.

Additionally, here's a resource you can browse that can help you to send email estimates and invoices using QBO for mobile: Email estimates, invoices, and sales receipts to customers using QuickBooks Online for mobile.

You can always have me if you have other queries in mind. I'll make sure to assist you in any way I can.