I use Printer Share, but through an access point. My Epson printer had wifi capabilities and is linked to the access point as well. Once my phone (and tablet) are connected to the network, Printer Share sees it and prints without needing to be connected to a computer. It does load a printer driver onto the phone, so you need to check and make sure your printer is supported.
I also have the Printer Share app loaded on my PC, so I can choose remote printing when not at home. It just goes through their servers to retrieve the IP address. It doesn't use a printer driver on the phone, just on the PC. Of course, you have to have a router for this to work.
If I remember correctly, Printer Share also can directly connect to bluetooth printers as well.
Printer Share works pretty well. It can access many different files and you can send things to the app through the Share menu option. It will link to your gmail app and print emails, although if you use a POP account and try to print from the Share option, it won't print HTML emails (at least not yet).