[Unity] PostProcessでビルド後に処理を差し込む ref: http://qiita.com/edo_m18/items/346439f7678218e85e69

post-process

// C# example:
using UnityEngine;
using UnityEditor;
using UnityEditor.Callbacks;

public class MyBuildPostprocessor {
    [PostProcessBuildAttribute(1)]
    public static void OnPostprocessBuild(BuildTarget target, string pathToBuiltProject) {
        Debug.Log( pathToBuiltProject );
        }
}

PostProcess-replace-sample

using UnityEngine;
using UnityEditor;
using UnityEditor.Callbacks;
using System.Collections;
using System.IO;

public class PostProcessTest {

    [PostProcessBuild (100)]
    public static void OnPostProcessBuild(BuildTarget target, string path) {
        #if UNITY_5_0
        if (target == BuildTarget.iOS) {
        #else
        if (target == BuildTarget.iPhone) {
        #endif
            RewriteObjCFiles(path);
        }
    }

    /// <summary>
    /// Rewrites the Objective-C files.
    /// </summary>
    /// <param name="path">File path.</param>
    private static void RewriteObjCFiles(string path) {
        string filePath = System.IO.Path.Combine(path, "Classes/UnityAppController.mm");
        if (File.Exists(filePath)) {
            ReplaceStringInFile(filePath, "OpenGLES", "OpenGLESHoge");
        }
    }

    /// <summary>
    /// Replaces the string in the file.
    /// </summary>
    /// <param name="file">File path</param>
    /// <param name="target">Target string</param>
    /// <param name="replaceText">Replace text</param>
    private static void ReplaceStringInFile(string file, string target, string replaceText) {
        if (!File.Exists(file)) {
            return;
        }

        // 置換後のテキスト
        string processedContents = "";

        using (StreamReader stream = new StreamReader(file)) {
            while (stream.Peek() >= 0) {
                string line = stream.ReadLine();
                processedContents += line.Replace(target, replaceText) + "\n";
            }
        }

        // 既存ファイルを削除し、置換後のテキストで新規作成
        File.Delete(file);

        using (StreamWriter stream = File.CreateText(file)) {
            stream.Write(processedContents);
        }
    }
}