UnityPDF - UnityPDF lets you merge, split, divide, rotate, protect PDF files and more.
DocuPUB - DocuPUB is an online file converter, file merger, file compressor, and file resizing tool.
PDFsam - PDFsam Basic, a free, open source, multi-platform software designed to split, merge, extract pages, mix and rotate PDF files
PDF Joiner - This online tool allows you to join several PDF documents into a single file, free of charge.
Clipperly - Convert, edit or optimize your files online. More than 400 different formats supported among documents, images, spreadsheets, ebooks, archives, presentations, audios and videos.
7-PDF Split & Merge - Functions: Split pdf-files, Merge pdf-files together