I use the built-in digital tuner in my Alesis GuitarFX to tune my Strat, then I tune my Ibanez acoustic-electric guitar by my Strat as I found the the digital tuner doesn't work quite as well with the acoustic-electric as it does with the Strat, with which the digital tuner has proven to be extremely accurate and precise. I find that this approach works very well in keeping both guitars in tune.
_________________________
Robert J. ("Bob") Welch III
"If you were the only person who ever lived, God still would have sent Jesus His only Son to die on the cross for YOU, because that is how much HE LOVES YOU!"