My iphone 4s won't let me download/send texts outside of my home?

I've just got a new phone. I have tried both the cellular data and Wi-Fi and neither work… My messages fail to send when I'm in the car and won't let me download any apps. My other iphone worked perfectly fine outside the house.

Check your settings. Maybe you have data or roaming turned off. If it works from home I assume its connecting with Wi-Fi.