JSFiddle - React, Tailwind, and code Playground

HTML

<button type="button" onclick="removeItem()">
  Remove
</button>

<br/>
<span></span>

JavaScript

$(document).ready(function() {
  var ios = [{
    "id": 1,
    "type": "free",
    "cat": "Diversi",
    "qty": 50,
    "date": "2016-11-02T09:51:48.872Z",
    "descr": ""
  }, {
    "id": 2,
    "type": "gree",
    "cat": "Lavoro",
    "qty": 40,
    "date": "2016-11-02T10:08:11.362Z",
    "descr": ""
  },
  {
    "id": 3,
    "type": "hree",
    "cat": "Lavoro",
    "qty": 33,
    "date": "2016-11-01T11:08:11.122Z",
    "descr": ""
  }];

  localStorage.setItem('ios', JSON.stringify(ios));

});


function removeItem() {
  var io = {
    "id": 1,
    "type": "in",
    "cat": "Diversi",
    "qty": 50,
    "date": "2016-11-02T09:51:48.872Z",
    "descr": ""
  };

  var ios = JSON.parse(localStorage.getItem('ios'));
  var index = ios.map(function(element) {
    return element.cat;
  }).indexOf(io.cat);
  alert(index);
  ios.splice(index, 1);
  localStorage.setItem('ios', JSON.stringify(ios));
}