Well now you only can purchase a byop sim from net10! Straight talk and net10 are sister company's of tracfone. Straight talk and AT&T had a dispute and split ties basically! You can buy a straight talk sim from eBay or amazon but the prices are unbelievable like 100$. Go with net10 I've been with them for years and there service is Great, there SIM cards are only 10 dollars on there website. Let me know If you do and I'll help you with the apn.