As the title suggest I have moved from Spark on a (what I'm guessing is a) galaxy S4 with spark software? (says spark when turning on).
Is there anything I will need to change to optimize the phone?
I also note that in certain areas of my house I lose signal (if I have it set to strictly 2degrees) and if I have it set to automatic it goes to roaming, is this how its meant to work?

Sorry if these are obvious questions but I've never actually changed providers on a phone without getting a  new phone.