JFYI: Xrite's device itself (the 1Pro, it's successor, the 1Pro2 (aka i1Pro Rev. E) or the latest i1Pro3) can be purchased as a simple measuring device or as a dongle.
The device itself is not too expensive. Last time I asked (some years ago) the i1Pro2 was at about 400€ here in Europe.
But most time the device acts as a dongle for Xrite's software i1Profiler, too. Dependimg on the "version" you purchased (Basic, Photo or Publish) some features get activated in i1Profiler, some not. The device itself stays the same (technically).
Most photographers/printmaker look for the "Photo" version. "Publish" can create CMYK and DeviceLink profiles, but you'd only need them in conjunction with a RIP or the like.
BTW: Same is true for Xrite's colorimeter i1Display Pro - it acts as a dongle for i1Profiler, activating monitor profiling options only.
Note 1: AFAIK, Xrite sells "normal" dongles (small USB sticks) for i1Profiler as well. So you could purchase the measuring device and the software features separately.
Note 2:: Some (not many) features of i1Profiler are "free", so you can use them without any dongle, be it a USB stick ir a measuring device.