Since the update and the new style invoice when I use the app to send invoice there is no option to add a PO or job J/N when using the computer both options are there

If you're looking to include a PO number or any other custom field on your invoice, you should be able to add this when using the mobile app. I'm here to help sort this out if you're not seeing the option and ensure that all features are correctly configured, Roger. 

To begin with, let's refresh your data so you'll see the latest available information. This will free up the storage without deleting your app's documents and data.To do so, follow the steps outlined below:

iOS

1. Go to Settings, then tap General.
2. Tap iPhone Storage, then tap the QuickBooks Online app.
3. Tap Offload App.

Android

1. Go to Menu, then tap More Options ⋮.
2. Tap Settings, then Refresh Data.
3. Tap YES to confirm.

Regarding your query about adding job J/N? Are you referring to the job costing feature? If so, the option should also be available in the app. However, if you mean something different, please provide more details so I can offer a more specific and useful response.

To give you more information on what's available on the mobile app, check out this article for reference: Compare Mobile App Features.

Additionally, you can learn how to receive and record invoice payments and manage payments, especially overpayments, tips, and credits. I got this resource for you: Record Invoice Payments in QuickBooks.

Let me know if you need further assistance when using the application or adding a purchase order. I'd be glad to assist you anytime.