A tool for everything?

9-Toolbox is a collection of ten calculators, converters, and other mini-tools (nine tools plus one bonus) that can help you with everything from divvying up a restaurant bill to measuring an incline while you're rappelling down an icy precipice.

9-Toolbox provides a utilitarian but surprisingly friendly interface for each of its tools, which include a Currency Converter (straightforward and automatically updating), Date Calc (to help you track the distance between dates), Days Until (a simple countdown tool), Holidays (major holidays by year for seven countries), Inclinometer (a flexible leveling tool with results in degrees, slope, and pitch), Loan (lets you compare loans side by side and calculate amortization), My Girl's Day (an unabashed, um, feminine calculator), Tip Calc (for splitting restaurant bills and calculating tip), Units (quick conversion between scientific units for area, length, pressure, temperature, volume, and weight), and Price Grab (a tool hidden on the app's info page that helps you calculate unit price between two different products). This app's usefulness will depend on how likely you are to use its various tools, but the tools are good quality and very easy to use.