Simple class for Screenshots in Unity, no need to attach it to any object, just call the Capture function and use, contains 2 constructors.

Screenshot.cs

using UnityEngine;
using System.Collections;

public static class Screenshot
{
	private static string GetTimestamp () {
		System.DateTime dateTime = System.DateTime.Now;
		return dateTime.ToString("yyyyMMddHHmmss");
	}

	private static string GetPath () {
		return Application.dataPath + "/";
	}
	
	private static string namePrefix = "Screenshot"; // Before the timestamp // Example "Gametitle_"
	private static string nameSuffix = ""; // After the timestamp

	// Default Capture
	// use like so Screenshot.Capture();
	public static void Capture () {
		string fullPath = GetPath() + namePrefix + GetTimestamp() + nameSuffix + ".png";
		Application.CaptureScreenshot (fullPath);
		Debug.Log ("Capured Screenshot: "+ fullPath);
	}

	// Capture with Custom Name
	// use like so Screenshot.Capture("FileNameHere");
	public static void Capture (string name) {
		string fullPath = GetPath() + name + ".png";
		Application.CaptureScreenshot (fullPath);
		Debug.Log ("Capured Screenshot: "+ fullPath);
	}
}