please help, apple orginal ipad , will not download any apps due to ios being5.1.1

I bought an apple ipad and it worked and full of apps at time of purchase, owner cleaned it for personal information and I can not down load any apps, status has been updated and is a 5.1.1 , apps say it needs to be a 6 or 7 ios, can any body help me or did I waste my money. Thanks !!!