Finally, after jumping through hoops I've found that PayPal Here, PayPal's credit card reader, works with a Tracfone smartphone.
Since I want to take credit cards and Paypal at the upcoming Llano Earth Art Fest, I decided I'd finally need to upgrade to a smartphone from my old flip phone. Before committing, though, I needed to know if Tracfone, which does not require a contract and works with prepaid data, text and phone minutes, would work with Paypal Here. I called Tracfone, they didn't know. I called PayPal, they hadn't tested with Tracfone. So I took a chance.
I ordered a TracFone Samsung S766C Galaxy Stardust from Tracfone and after learning to use it, checked with PayPal one more time. They still didn't know, so I took a chance and ordered the card reader. After something of a learning curve, I've found it works. It'll need a bit more testing, but it looks as though it's going to serve me well at the festival, and pretty much anywhere else.
For an investment of $50 I got a nice phone with no contract or monthly charges and a payment system that's going to work well. I love Paypal's features and also use Paypal as my payment solution on my Dotrageous site, partnered with the Ecwid Storefront/Shopping cart.