If I use the iPhone app where is the option in expenses for ‘paid with cash’ ?

Hello there, @evehealey.

Let me guide you on how to select the "paid with cash" option when creating an expense. Here's how: 

1. In the Hamburger button, tap Expenses.
2. Click the Create (+) button. 
3. Select the Other tab and select an account. 
4. Enter the remaining information, including who you paid.
5. Tap Done and Save.

I've attached an article you can use about how to attach a receipt photo, split, or edit expense, as well as some FAQs about the app: QBO iPhone in-product topics. 

Please know that I'm just a few clicks away if you have any other questions. I'll be happy to help you some more.