For my titration data, I used SQUAD. It's fairly simple to use and is accurate for a wide variety of media. A good reference for you to find an applicable program would be "Computational Methods for the Determination of Formation Constants" by Leggett. Check that against your program requirements.
For UV-Vis or many other type of specroscopic titration data you can use HypSpec software. Check through the following website. The best I have ever known.