Customers can't view invoices on a mobile

I'd be glad to guide you on how to view invoices on mobile, @BikeShopDave.

We can perform some troubleshooting steps to fix this. There are times that the browser is full of frequently accessed pages, thus causing some unusual responses. In this case, we can clear the apps cache files. Doing so helps in fixing any sorts of errors in the system. Here’s how:

1. Click the Help menu at the top of the screen.
2. Select the Rest App Data option on the drop-down selection.

If you get the same result, uninstall and reinstall the QuickBooks Online app. This is to ensure you get the most recent version of the application. 

Here's a great source that you can visit to help you record your self-employed income and expenses, track mileage, and prepare your Schedule C: QuickBooks Self-Employed Overview.

Let me know if you have other QuickBooks concerns. I'll be happy to help you out. Have a nice day.

If you could help, that would be great.

ive sent test invoices & ‘view invoice’ is greyed out & doesn’t link through to the pdf, so can’t see any details.

works ok on a computer, but the vast majority of my customers use mobiles

Thanks for getting back here, @BikeShopDave.

Since resetting the app data does not work. I highly recommend reaching out to our technical support team to investigate the root cause of the issue. They can pull up your account and provide steps to fix it for you. To connect with them, follow these easy steps:

1. Click the Help icon.
2. Select Contact us.
3. Enter Cannot click the View invoice button in the What can we help you with? box.
4. Hit Let's talk. 
5. Choose either Start a chat or Get a callback.

In the meantime, have your customer view the invoices using a web browser.

You can also visit our Categorise transactions page to help you in managing your QBSE account. This page includes steps on how to record your self-employed income and expenses, and prepare your Schedule C. 

Let me know how this goes and leave a reply below. I'm always here to help you. Have a good one.