I've been selling a lot of electronic tuners lately, and it seems that every month or so another manufacturer comes out with a tuner that is the next great thing, with more bells and whistles, and with correspondingly higher prices, or with tuners at a competitive price that are the same as other tuners which only confuses the average buyer. I have had to take more time selling tuners and metronomes to people than an instrument. People get easily confused when presented with so many choices, and when you get down to it, a tuner is not a complex thing. You turn it on, if it's a tuner with a microphone built in, you play the note until the display either shows the note you are looking for, or the needle in the display reads the letter and is in the middle. However, if there are any extrenuous sounds, it will interfere with getting it tuned accurately. Clip-on tuners go by vibration of the instrument for more accurate tuning. I will not recommend any tuners because I really don't use them, and while it seems that a lot of educators are stressing the use of a tuner, it is a bit different for wind and brass players. This is another subject with which I differ with a lot of teachers.
Lately, I have saxophone teachers and their students coming in and asking for tuners. Okay, my job is to sell them, but it seems that they are bogging down their students by having them play every note on the saxophone and match it with a tuner. Let's start with the fact that no saxophone plays in tune to begin with. No wind or brass instrument plays perfectly in tune. When manufacturing the saxophone, the builder makes compromises somewhere when placing toneholes for the best balance of the scale. The rest will be up to the player, with their mouthpiece, reed and lip and more important, their ear. Anyway, many young teachers have their students going on every note and trying to match it to the tuner, which you can and should to some degree. I find that using a tuner to match every note in the scale is a tremendous waste of time. On the alto saxophone, I tune to pitch A=440 on the tuner or using a pitchfork and playing F# on the alto or baritone, or G on the tenor and soprano. Then I move the mouthpiece until it matches. You can mark the place on the cork with a pen or knife where the sax will play best in tune. If you do that correctly, and your saxophone isn't a piece of junk, it should play well enough in tune throughout the scale as long as you are also using your lip and your ear.
Players need to be able to train their lip and hearing so they know immediately whether or not their intonation is off. When playing a scale, you can hear the relation of one note to another, and if a note isn't attuned to the other notes in the scale, then you know that either you're playing the wrong note, or you need to either use more or less lip pressure according to where in the scale you are. Generally you tighten your lip when hitting the higher notes and loosen the lip when playing the lower ones. There is really no need to spend an inordinate amount of time tuning every note to the tuner, just more time listening to what you're playing. If you have the basic tuning done correctly by positioning your mouthpiece on the neck cork to match F# or G, then just pay attention to what you're playing when playing a tune or practicing your scale and chord patterns. Learn to attune your ear, then learn to trust your ear. The old masters didn't have modern tuners and they played in tune, many on old saxophones that supposedly have faulty intonation according to some modern players. What the old masters had, and what every musician needs to develop is their ear so they can always tell if they are out of tune or not.
I don't claim to have perfect pitch, and very few of us do, but all of us have relative pitch, and we can hear when one tone is different from another. If you continue to practice and play, you will hear and know if something is amiss. You don't need to stop and pull out a tuner every time and see. Too many players are relying on the tuners but are still not using their ability to hear and recognize when a note is in or out of tune. I prefer the pitchfork, because it is simple, accurate and it never needs batteries and it fits neatly into my case. It also helps train my ear. Tuners are useful only if they help you eventually hear the right note and then you no longer have to rely on it. If you need to use a tuner each and every time you play, then you're not really listening. There are some who may take issue with what I say, but that's my story and I'm sticking to it.