Cam scan, and Images can turning your images to pdf files.
also you can add images from photo library to convert them to pdf file.

You can easily manage them.
You can share files.
You can delete files.
You can search for files.

Now it's more powerful, and more options.
You can add more pages in same pdf file.
You can remove a page you don't need.
You can change page number as you want.

Just with one long press, go inside you pdf file and tap long and you'll get the options.