Autocomplete is not working in my sharepoint-hosted app why?

In my app.js i have this code

$(function () {
var availableTags = [
"COBOL",
"ColdFusion",
"Erlang",
"Fortran",
"Groovy",
"Haskell",
"Java",
"JavaScript",
"Lisp",
"Perl",
"PHP",
"Python",
"Ruby",
"Scala",
"Scheme"
];

$("#tags").autocomplete({
    source: availableTags,
});

});

in my default aspx i have this code

i have an input id=tags

Right now nothing happens when setting a breakpoint inside my function nothing happens it dont go in there,

I also have this scripts in my default.aspx

http://ift.tt/1dLCJcb

http://ift.tt/1vj7BK9