Hello Sumner711, this watch is 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. For a list of compatible smartphones and features, please visit https://www.samsung.com/galaxywatch/device-compatibility. For best results, connect with compatible Samsung Galaxy smartphones. You can quickly and easily view incoming messages on this watch and send replies, and you won't even need to take out your phone. Here is a link (https://www.samsung.com/us/support/answer/ANS00078022/) to an article that goes deeper into messages on this watch. You can also make phone calls from your wrist. Follow this link (https://www.samsung.com/us/support/answer/ANS00061408/) to learn more about this feature. ^Elizabeth