Calcbot for Apple Watch - Calculate, convert, and split tips from your wrist
Tip Calculator - The ultimate tip calculator with split function
SpeQ Mathematics - SpeQ is a small, extensive mathematics program with a simple, intuitive interface.
Qalculate! - Qalculate! is a multiplatform multi-purpose desktop calculator.
Toothpick - Calculate your tip based on the server's gender
NumWorks - The graphing calculator that makes learning math easier.