e

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  msg: null,
  actions: {
    fixSpelling(msg) {
      if(msg === "3") {
      	msg = "e";
      }
  		this.set('msg', msg);
  	}
  }
});

models.my-model.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  
});

templates.application.hbs

<h2>Use "3" for your broken "e"</h2>
{{ textarea value=msg cols="60" rows="6" keyPress="fixSpelling" }}
<br />
<br />
{{ msg }}

twiddle.json

{
  "version": "0.10.5",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.8.0",
    "ember-data": "2.8.0",
    "ember-template-compiler": "2.8.0",
    "ember-testing": "2.8.0"
  },
  "addons": {}
}