Documents by Readdle - A central hub for all your files.
pdflayer - Free, powerful HTML to PDF API supporting both URL and raw HTML conversion. Unlimited document size, lightning-fast and compatible PHP, Python, Ruby, etc.
FileApp - FileApp is an iPhone and iPad File System and Document Viewer.
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
Documents Pro 7 - The ultimate all-in-one mobile office suite for the iPhone and iPad with 8 premium apps in 1.
Tcpdf - TCPDF: Open Source PHP Class for generating PDF documents