This script runs through all the devices and generates a HTML page, viewing all the images

DeviceSwitcherForSubliminal.rb

require 'JSON'

class Runner
  def Runner.run
    system("xcodebuild clean")

    config = {
      "devices": [
        "iPhone 6 Plus (8.1 Simulator)",
        "iPhone 6 (8.1 Simulator)",
        "iPhone 5s (8.1 Simulator)",
        "iPhone 4s (8.1 Simulator)"
      ],
      "languages": [
        "de"
      ],
      "ios_version": "8.1"
    }
    app_id = File.read("./Resources/appID.txt").to_i

    devices = config["devices"]
    languages = config["languages"]
    ios_version = config["ios_version"]
    output_path = ENV["output"] || "./reports/"
    output_path = "#{output_path}/#{app_id}"

    project = "GCSpecs"
    scheme = "Integration"

    FileUtils.rm_rf(output_path)

    run = 0

    languages.each do |language|

      # Switch the language by editing the xcscheme
      path = "./#{project}.xcodeproj/xcshareddata/xcschemes/#{scheme}.xcscheme"
      content = File.read(path).gsub(/AppleLanguages\ \(..\)/, "AppleLanguages (#{language})")
      File.write(path, content)

      sleep 2
      puts `open "/Applications/Xcode.app/Contents/Developer/Applications/iOS Simulator.app"`
      sleep 2

      devices.each do |device|
        puts "Running on #{device} in language #{language}"


        run_output = "#{output_path}/#{run}"
        FileUtils.mkdir_p(run_output)

        `killall "Instruments"`
        `killall "iOS Simulator"`
        `killall "xcodebuild"`
        `killall "subliminal-instrument"`
        
        command = "
                \"./Pods/Subliminal/Supporting Files/CI/subliminal-test\" \
                       -workspace \"#{project}.xcworkspace\" \
                       -scheme \"#{scheme}\" \
                       -sim_device \"#{device}\" \
                       -sim_version \"#{ios_version}\" \
                       -output \"#{run_output}\""

        IO.popen(command) do |fd|
          until fd.eof?
            puts fd.readline
          end
        end
        
        puts `
                  "./Pods/Subliminal/Supporting Files/CI/subliminal_uialog_to_junit" \
                      -i "#{run_output}/Run\ Data/Automation\ Results.plist" \
                      -o "#{run_output}/junit.xml"
            `
        run += 1
      end
    end

    # Create directory listing of this folder
    files = []
    html = ''

    Dir.glob("#{output_path}/*/Run\ Data/*.png") do |file|
      unless file.to_s.include?"Expecta Error"
        puts "Found screenshot #{file}"
        path = file.gsub("#{output_path}/", '')
        files << path

        image_url = "/screenshots/#{app_id}/ios/#{path}"
        html += "<a href='#{image_url}'><img src='#{image_url}'></a> "
      end
    end

    File.write("#{output_path}/files.txt", files)
    File.write("#{output_path}/index.html", html)
  end
end

task :default => :do_it

task :do_it do |t|
  Runner.run
end

Please use snapshot instead