Brand new iphone 4s freezing on facebook?

I got my iPhone 4s on sunday and the phone overall is great. The only problem is when I go onto the Facebook app it either takes a while to load or just completely crashes and sometimes just closes itself, I have other apps eg. Instagram, snapchat, whatsapp and I've had no problems with them its just facebook:/ my question is, can I solve the freezing? And is it my phone or facebook?

There's a bag on the app, it's very common