How to change the old apple ID on my iphone so I can update the apps from store?

My cousin gave her Iphone4 to me, i already changed the apple ID but when i tried to update the apps the she installed, it's still showing her apple id (with password required). How can i change it so i can update the apps.
*Even on candy crush, it shows her picture & her friend's instead of mine. I think that's the reason why I can't proceed to the next level. It keeps asking me to ask my friends on facebook*

You might have to delete the apps and redownload or ask her for the password but I think you should check settings again and make sure that you made an id

Old I'd remains in settings