Save your money and just use the phone app. Pitch isn't the most important factor.
If I'm reading or talking about tech issues my pitch analyzer tells me I'm averaging 175-180, just under the female range, yet I still sound female. Early on I had just the opposite, I would get averages in the 190's and not sound so good. It's more about resonance and getting your voice out of your chest. Now I hardly ever use the pitch analyzer and rely on feedback from the voice recorder.
