Samsung's story with Bixby is a long and complicated one. To make it short: Bixby was not ready in the US when Samsung launched the S8, so developers began devising ways to repurpose the dedicated Bixby key to perform more useful actions. Since then, Samsung's efforts to prevent developers from remapping the key have failed to do so every time. T-Mobile's latest firmware update for the Galaxy S8 and Galaxy S8+ (released on July 8 blocked the last known remapping method and an updated one is already out. Apparently, all that needed to be done was to enable a "compatibility mode" for the app...
Source: http://www.gsmarena.com/bixby_key_remapping_works_again_despite_samsungs_continued_efforts-news-26137.php
