Hi @PK49,
It appears your Invoices tab is set in a descending order via its Date column.
What you need to do to reverse this is to click the Date column. It will then set the invoices into ascending order. Now, every time you open the Invoices tab, the filter you set will become the system's default.
So you can send invoices on the go, I suggest you use the QuickBooks Online (QBO) mobile app. Check out this article to learn of its features: Features of the QuickBooks Online app.
Post a reply if you have other concerns with your QBO company, and I'll handle it for you.