Recently, i am unable to select some options when adding an expense. When viewing on computer, the options are there (ie tax code or categories) but not on mobile.

Hello accounts580,

Glad to have you join the Community! QuickBooks is designed to be an easy-to-use program. It's vital you're able to experience this benefit without running into issues. Rest assured, I'll be happy to help so you're on the right track. 

To get started, it's important to make sure the invoice has inactive data. In case there isn't any inactive data upon checking, I recommendI recommend uninstalling and reinstalling the app. This is a good way to troubleshoot bugs that affect the app. By reinstalling it, this ensures you're on the latest version of the mobile app. You can visit these links to reinstall the QBO mobile app:

• Android app via Google Play.
• iPhone, iPad, and Apple Watch apps are via the iTunes App Store.

Give this a try and feel free to keep me posted on how you make out. I'll be a message away.