Samsung Galaxy S4 Mini Duos GT-i9192 Factory Unlocked International GSM Dual Sim Cell Phone - Retail Packaging - Black A petite 4" screen with Super AMOLED display, which means vibrant amazing colour and clarity. HD video capability and powerful 8-megapixel camera let you capture each beautiful detail, in beautiful detail. Let your phone keep track of all the steps you've taken in a day, or sync it with external monitors for blood sugar and blood pressure via Bluetooth. Unlocked cell phones are compatible with GSM carriers such as AT&T and T-Mobile, but are not compatible with CDMA carriers such as Verizon and Sprint.