Yes, you can have multiple buttons on your navigation bar. You can either add them on the right side or left side of your bar. To do that, you need to create multiple bar buttons and add them as an array. Something like this:
UIBarButtonItem *actionBtn = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction target:self action:nil];
UIBarButtonItem *addBtn = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:nil];
UIBarButtonItem *bookmarksBtn = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemBookmarks target:self action:nil];
self.navigationItem.rightBarButtonItems = @[actionBtn, addBtn, bookmarksBtn]; //Considering that you want to have three buttons on the right side.