Best How To :

Airspeed Velocity gave you the answer:

var arr: [Int] = [1,2,3,4,5]

var stringArray = arr.map 
{ 
  String$($0)
}

Or if you want your stringArray to be of type [String?]

var stringArray = arr.map 
{ 
  Optional(String$($0))
}

This form of the map statement is a method on the Array type. It performs the closure you provide on every element in the array, and assembles the results of all those calls into a new array. It maps one array into a result array. The closure you pass in should return an object of the type of the objects in your output array.

We could write it in longer form:

var stringArray = arr.map(
{
  (number: Int) -> String in
  return String(number)
})

EDIT:

If you just need to install your int values into custom table view cells, you probably should leave the array as ints and just install the values into your cells in your cellForRowAtIndexPath method.

func tableView(tableView: UITableView, 
  cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell 
{
  let cell = tableView.dequeueReusableCellWithIdentifier("cell", 
    forIndexPath: indexPath) as! MyCustomCellType
  cell.textLabel?.text = "\(arr[indexPath.row])"
  return cell
}