Universal Tuner 4+

It's hard to find a free tuner app that will let you pick input devices. Occasionally this app crashes when changing that input. Once I get it receiving the input from my audio interface, it works great.

Learning to tune pianos.... Not an easy thing to do, especially when the tuning app won't pick up the high and low octave. The pathetic chinese one on my older iphone works much better to pick up the sound than this software does.

As I'm using a 2020 Macbook Pro, the problem really can't be the microphone. I mean, c'mon, the mics in these things are amazing. However, even were that the case, it won't let you select another audio input without purchasing the 'upgrade'! I'm sorry, but I am not going to buy a software that hasn't worked well yet, in hopes that it's 'premium' version will!
All this to explain, that it doesn't work for me. Hopefully it will work for you, because if so, it's better then investing $50 in a higher end software. (which is what I will probably be doing)

I bought it right away. Very few apps have this level of professionalism; the developers of this tuner have started something sweet.

The developers even published well written documentation for their app! Amazing!!

I just hope they aren't finished yet. There are a few minor features that I'd love to see.

1. I really need the ability to create and save my own custom tunings. This app doesn't have any of the tunings that I'm currently experimenting with, so that's frustrating.

2. I really need to tune lower than 428 for the concert pitch. That sounds strange, but I play classical guitar and I simply cannot tune up to New Standard tuning without lowering the relative pitch. Several other tuner apps go as low as 400 hz.

I also play electric guitar with 13 guage strings, which has led to similar issues with needing tune down.