I own a Nexus 5 but just bought a new phone (which is also unlocked gsm). I have the Simple Basic plan with tmobile and it suffices. After checking ebay and seeing what I would get by selling the Nexus, I am wondering if I should just keep it and use it when I travel and simply buy local SIM cards and prepaid plans. I live in Los Angeles, am going to NYC in the summer and want the web available to check subway times and other mundane travel-related stuff. But I will also need a phone when I travel abroad and I'm trying to figure out the best approach I can take to (1) make use of the Nexus and (2) contain phone charges. Any ideas would be appreciated. I'm a bit stumped.