The 'F' in FPDI stands for 'free': you may use it for any kind of project and adapt it to your needs -the license conditions of ASL 2.0 are met nevertheless.
PDF Documents > 1.4
Do you need support for PDF documents with a version higher than 1.4? Check out the new FPDI PDF-Parser!
FPDI and tFPDF
This example shows how FPDI works together with tFPDF. tFPDF is a version of FPDF, which supports UTF-8 and font-subsetting.