Last year Sony introduced the "Concept for Android" initiative, rolling out an experimental build of Marshmallow for the Z3 series for eager people to test. And now it's following that up with a new "Concept for Android" release, this time based on Nougat and meant for the Xperia X. This comes only a few days after the company made the first beta build of Nougat available for the Xperia X Performance. The concept software for the Xperia X is only available for single-SIM units sold in Europe and bearing the model number F5121. Do note that certain "market and/or network operator exceptions...
Source: http://www.gsmarena.com/sony_outs_concept_for_android_software_based_on_nougat_for_xperia_x-news-21527.php
