I've never needed an electronic tuner... in fact, on one occasion (in the mid 1980's) a friend was tuning her guitar to an electronic tuner, and I said 'That's sharp!' to which she retorted that the tuner said it was in concert pitch!

So I asked her if the battery was okay, and she pressed the battery checker - nope! The battery was nearly flat - making the tuner read sharp!

'Perfect Pitch' can be learned - if you are driving in your car, you always know what note the next song starts on when you're playing your favourite tape/CD!