Here's some good news if you own the Samsung Galaxy S4 Google Play Edition, the one and only such device put out by the Korean company. The handset hasn't been on sale for a few months now, but if you got it earlier you'll be happy to know that an update to Android 5.1 Lollipop is headed its way at some point in the near future. As Google handles such rollouts for the GPE devices, this is no surprise. What has been surprising however is that the S4 GPE is still stuck on Android 5.0 for whatever reason. This fact has led many to question whether it will ever move past this version. And the answer is yes it will. According to some unnamed sources, the Android 5.1 build for it is ready and could start rolling out at any time. Which it should, since the Galaxy S4 is the only GPE phone not to have received this update...
Source: http://www.gsmarena.com/samsung_galaxy_s4_google_play_edition_will_get_android_51-news-12077.php