I have (used to have) a Motorola MAXX. If I get a Samsung phone, will the SIM card work in it?
There are standard SIMS, micro SIMS and nano SIMS - and it looks like the MAXX uses a nano SIM (the smallest) If the SIM card you have doesn't fit the new phone, and the phone you get does not have one pre-installed, you can always get one free at a corporate store. There are also adapters that allow you to use a nano SIM in a phone that takes a larger card.
It depends on if they are the same size SIM cards.