connectivity

If it's Android OS, most of your android devices should get connected to it, likewise if it's Apple OS most of the Apple devices should be compatible with it. This is how you make a wise decision while planning to buy the best smartwatch for yourself.

Apart from this, see if the smartwatch offers other modes of connectivity such as Bluetooth, Infrared, NFC. Some of the smartwatches also support the calling feature as they support a SIM card and have their own independent cellular connectivity.