Hi there, Danorion. I can show you the steps in sending an invoice link in QuickBooks Online (QBO).

The ability to send an invoice link is only available in QBO. Sending an invoice link through QBO is still unavailable. I recommend sending feedback to our product developers to inform them about your request to change the phone number format. This way, our Product Engineers can consider adding this in future updates.

Here's how:

1. Sign in to your QBO account.
2. Click the Gear icon at the top, then Feedback.
3. Enter your comments or product suggestions.
4. Press Next.
    

Once done, our designated team will review it. You can track your future requests through the QuickBooks Online Feature Requests website.

You can consider browsing our QuickBooks App Store to find an application that has the ability to send estimates and invoice via text message. 

In the meantime, you can consider accessing your QBO through the desktop to get the invoice link and send it via text.

Here's how:

1. Log into QuickBooks Online. Then select Sales.
2. Click invoices. Then, look for the invoice you want to share a link.
3. Hit the dropdown button under the Action column.
4. Select the Share invoice link.
5. There will be a pop-up window. Click the Copy link button, then click Done.
6. Send the copied link to your customer through text.

I've also added a screenshot for your visual reference.

In addition, you can refer to this article to learn what the feature supports on mobile devices in QBO mobile: Compare mobile app features.

Get back to this post if you still have concerns about the features of the QuickBooks mobile app. I'm always here to help you.