LensCalcToolsPro is an optical calculator app with a full set of lens design tools. It provides back focal length and principal plane shift estimates for packaging checks. The app calculates equivalent f-number, lateral magnification for finite conjugates, and angular magnification for afocal systems. It includes telephoto ratio analysis, back focus optimization, and spacing solutions for a target effective focal length. Field of view can be related to sensor size for framing and coverage. Chromatic focal shift is estimated using Abbe numbers to study color blur. Petzval curvature and distortion are also approximated to guide early design trade-offs.