4 tools
Free, portable PDF splitting/merging utility (library, console, and GUI); also converts JPG images to PDF.
Go PDF library (pure Go): generates reports/invoices with styled text and tables; creates and fills forms; merges, splits, reorders, and rotates pages (incl. N-up layouts); extracts text (with position/formatting), images, and tabular data to CSV; adds/converts images to PDF; removes or adds password protection; validates and applies digital signatures; compresses/optimizes files; adds watermarks; and supports CCITTFax/JBIG2 image decoding.
JavaAndroid PDF toolkit centered on creating PDFs from camera/gallery images (and converting text files to PDF), plus managing existing PDFs: merge, split, compress, remove/rearrange/rotate pages, extract images, and encrypt/decrypt.
PythonSmall python-gtk application, which helps the user to merge or split PDF documents and rotate, crop and rearrange their pages using an interactive and intuitive graphical interface. A GUI front-end for pikepdf; can also import images into a PDF when img2pdf is installed.