I've never used a bluetooth obdii scanner, myself, but if you want something specifically for ford, I'd strongly recommend getting an ebay elm327 usb to obdii adapter (around 12 bucks) and downloading forscan for free from their website. That's what I use and it's paid for itself on the first use. It can look at every single thing on the Ranger. It'll give you codes, allow you to reset dtc codes, run self tests on a given system, and even do some pats work. Bonus if anyone else you know has a ford vehicle, as it'll work on any ford 1996 or newer. Heck, it even works on my mother's 2010 Lincoln MKX, so add mercury and ford to that list.
Extra bonus is that elm327 will be compatible with the grand majority of other software out there, from generic CEL programs to the more expensive and versatile flavors of scan software.