Hi there, @SophiaGTP. Thanks for getting back here in the Community.

Although QuickBooks Online (QBO) is an accounting software accessible anytime, anywhere with an internet connection, there are still limitations depending on where we access it. With that being said, I'd like to inform you that opening QBO on an app offers a limited experience rather than accessing it through the web. 

QBO app is a limited version of the program that offers the most basic features and the most needed ones. Thus, if you want to have access to all of its advanced features such as utilizing the custom fields to add the arrival and departure time on your invoices, you need to perform it on the web only. I can see how this feature can benefit your business as this will make your invoices more detailed, however, it isn't available in the QBO app. You may want to use the web instead.

Additionally, should you want to create recurring transactions such as invoices in QBO to automatically record sales and expenses, feel free to browse through this article that I've included: Create recurring transactions in QuickBooks Online.

I'll be here in case you need a hand in managing your invoices in QuickBooks Online. It's my pleasure to make sure you accomplish your QuickBooks-related tasks. Assistance is just a reply away. Keep safe and have a good one.