Many kits include a 3-in-1 SIM that fits the common sizes—standard (mini), micro, and nano.
These kits work with most phones and tablets, including most unlocked devices and unlocked GSM phones.
Bringing your own phone means you insert the SIM into your existing device and either port your current number or select a new number during activation.
It means the plan allows you to share your mobile data with other devices via a hotspot at no additional charge, per the plan’s terms.
Many kits let you port (transfer) your existing phone number or choose a new number when you activate service.