On all of our mobile devices if we want to amend the template when sending an invoice or estimate it will not let us work on it and instead always sends us to the bottom?

The QuickBooks Online mobile app uses a fixed layout, so custom form templates cannot be edited directly inside the app. You can customize your invoice and estimate templates by logging in to QuickBooks Online through a web browser.

If instead you're editing the details of an individual invoice or estimate (not the template itself) and the screen keeps jumping to the bottom, you can refer to this article for troubleshooting steps: Fix common issues in the QuickBooks mobile app.

Feel free to return if you have follow-up questions.