Silently, the Google this week launched another app on the App Store. This is the calculator Ivy.
Ivy is an experimental large number calculator.
It uses exact rational arithmetic so that it can handle precise arbitrary. It also supports high precision of irrational values resulting from operations like square root. Values can be entered as integers, rationals or floating point numbers.
Some features of the calculator include: arbitrary floating point formatting, rational exact arithmetic, high precision irrational arithmetic, APL-type vector, matrix, trigonometric, logarithmic and exponential functions.
If you view the page of the app in the browser (iTunes Preview) you will notice that, in addition to Google, Go Authors is listed as a seller (seller). According to 9to5Mac, this is a reference to The Go Project, an open source programming language developed by Google employees and contributors.
There is a possibility that the app was developed as a complementary tool to the project, the app itself was even written using this programming language.
For those interested, there is a complete description of the calculator's internal engine / mechanism here.