Hello Cathy, thanks for asking! This watch will be compatible with Samsung Smartphones, Non-Samsung Android Smartphones (Android OS 5.0 and above RAM 1.5GB and above), iOS 9.0 and above iPhone 5 and above. This model connects to your phone via Bluetooth which allows you to answer calls and messages. Please follow this link (https://www.samsung.com/us/support/answer/ANS00061408/) to learn more about making calls and this link (https://www.samsung.com/us/support/answer/ANS00078022/) to learn more about messages. ^Elizabeth