keydown should work, but you could use the input event which seems to have undesired effects on Android mobile…
To get the code of the pressed key use the jQuery’s normalized Event.which
Android Chrome tested:
Using input Event (e.which gives always 0 so it seems like a bug on android devices)
jQuery(function($) { // DOM ready and $ alias secured
$('#buscar-producto').on('input', function(e){
var key = e.which || this.value.substr(-1).charCodeAt(0);
alert( key )
});
});<input type="text" id="buscar-producto" placeholder="Buscar...">
<script src="https://code.jquery.com/jquery-3.1.0.js"></script>Using keydown (works as expected)
jQuery(function($) { // DOM ready and $ alias secured
$('#buscar-producto').on('keydown', function(e){
alert( e.which );
});
});<input type="text" id="buscar-producto" placeholder="Buscar...">
<script src="https://code.jquery.com/jquery-3.1.0.js"></script>