Samsung's Galaxy A51 has been up on sale throughout UK since February 2020 and it entered the market in the United States through April and retails at about $399.99/£329. Knock, knock. Who’s there? KNOX, your phone security guard! Learn more: https://t.co/LyYC628mfD#Samsung #GalaxyA51 #GalaxyA71 #AWESOME pic.twitter.com/BGkmZkRMQO—