As for a tuner, Boss TU-3, Korg Pitchblack, Peterson Strobostomp, TC Electronic PolyTune 3, are all fine. You could even go with the Ernie Ball volume pedal that has the tuner display on it. It mostly comes down to what display you like the best and is going to be easiest for you to use on stage.
Peterson owns the standard for tuning. Not literally, but they’ve been doing it so long and the pedal is really nice. If I got one I would keep it at the house for doing intonation instead of taking it on a stage where people will spill beer on it. Unless you were heavily into using the sweetened tunings for your guitar. It just seems like overkill for the stage.
The Boss is simple and built like a brick. This is the one I have and would guess more people have used on stage than any other. When you see the light go green, you know your good. It can also be used to defend yourself if the crowd takes issue with your playing.
The TC Electonic has a good following for its ability to show which string is out of tune with a single strum. I never figured out how to turn the poly tuning off and found it annoying when tuning for bass. Could have been user error but I returned it and got the Boss.
The Korg is simple and has a really nice display. If I didn’t have a tuner already, I would probably get this one. That display is really nice and my eyes aren’t.
Looper’s coming up next…