I use a Peterson strobe tuner on my smartphone, it's really good.
I've also coded my own strobe tuner to learn more, unfortunately no mobile version yet.
In my experience, electronic tuners suck at accurately detecting the note played.They often pick up harmonics as the note.
The low b on my 5 string bass is often identified as an f by electric tuners.
They also just aren't very accurate when they do detect the right note. I've never used a tuner where my cello is actually in tune when it says it is, always requires tweaking.
The most popular tuner of all time is the BOSS pedal, and the LED lights are too far part from eachother, it's simply not granular enough to really get in tune to my ears.
Agree that most leave something to be desired. TC Electronic polytune is great and I also use the pedal to mute my signal. I'm surprised to say this, but my favorite tuner is the one in the L6 Helix.
But in all seriousness, if you are looking for a good guitar tuner, a lot of the ones on the market are actually not very good.
I highly recommend TC Electronic for clip-on tuner, or Sonic Research or Peterson for pedal tuners.
source: playing guitar for 32 years