Font Size Calculator - iPhone
People choose font sizes every day, yet seldom have a good reason for their choices. The Font Size Calculator provides a simple yet powerful tool for making statistically-informed font-size decisions.
Compatible Devices: iPhone and iPod Touch
A Tool for DesignEnter viewing distance (in feet or meters) and the Font Size Calculator computes the minimum font size. Adjust this result based on lighting conditions and reliability.

A Tool for AnalysisEnter font size of an existing design (in points, inches or cm) and the Font Size Calculator computes the maximum viewing distance. Adjust lighting conditions and reliability to determine the effectiveness of the design at different viewing distances.

Review the science behind this app.
Credits
Development: Joe Maurer
Project Management: Jeff Cortez

Paul Chang's thoughts
There was a comment at the iTunes Store regarding the effect of Photoshop file resolution on point size. Perhaps our “Points” measurement is misleading. In the context of the Font Size calculator, a point is simply 1/72 of an inch.
If this is confusing, forget about the Points units and use inches or centimeters. Then, knowing the physical size requirement for the font, make the necessary calculations for the particular resolution setting.
If the requirement is for a font size of 0.5 inch and the resolution is 300 pixels per inch, then the font should be 150 pixels tall.
Hope this helps.
Paul
Millsky's thoughts
Good job. Thx
Short distances?'s thoughts
When I enter 0.5 ft, I get results like 1 pt. type. Is that correct ?
Thanks….