Absolutely. You can try Joist Pro Elite free for seven days, no credit card or signup required.
To get started, just go ahead and use any one of the Pro Elite features now available in your Joist App. You'll see a purple PRO Elite badge next to any feature included in Joist Pro Elite, like the Change Orders feature for invoices, shown here in the iPhone App.
You'll be presented with the option to upgrade to Pro Elite, but just tap the "I'll upgrade later" option at the bottom of the screen to begin your trial and explore all the benefits of Joist Pro Elite for seven days.