<button id="callback" class="phone">Первая</button>
<button class="phone">Вторая</button>
<button class="phone">Третья</button>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<script>
$(function() {
$(".phone").click(function () {
alert (this.innerText);
});
});
</script>