xCalculator

Support for all basic operators.
Progressive calculations.(results appear on top and change side by side as you change the expression)
Provides commonly used constants.
Switch between different angle measurements with ease.
Scientific Mode that provides various trigonometric, hyperbolic and inverse functions, calculus and iterated operators, much more.
Provides variable support.(only 1 variable)
Precision settings for precise calculations.

Unit Converter
Currency: Conversions are handled through exchangerate.host API and requires an Internet connection.

Length: Conversions to and from Femtometres, Picometres, Nanometres, Micrometres, Millimetres, Centimetres, Decimetres, Metres, Decametres, Hectometres, Kilometres, Inches, Feet, Yards, Miles, Nautical Miles, Megametres, Gigametres, Terametres, Petametres

Volume: Conversions to and from Microlitres, Drops, Millilitres, Cubic centimetres, Decilitres, Litres, Cubic metres, Cups(US), Cups(UK), Pints(US), Pints(UK), Quarts(US), Quarts(UK), Gallons(US), Gallons(UK), Dry, Liquid, Federal and Oil Barrels(US), Barrels(UK), Cubic inches, Cubic feet, Cubic yards, Teaspoons(US), Teaspoons(UK), Tablespoons(US), Tablespoons(UK), Fluid Ounces(US), Fluid Ounces(UK)

Area: Conversions to and from Square millimetres, Square centimetres, Square decimetres, Square metres, Square decametres, Square hectometres, Square kilometres, Hectares, Square miles, Acres, Square inches, Square feet, Square yards, Square nautical miles, Dunams, Tsubos, Pyeong, Cuerdas, Square megametres, Square gigametres, Square terametres, Square petametres

Weight/Mass: Conversions to and from Femtograms, Picograms, Nanograms, Micrograms, Carats, Milligrams, Centigrams, Decigrams, Grams, Decagrams, Hectograms, Kilograms, Newtons(Earth), Tonnes, Ounces, Pounds, Stones, Tons(US), Tons(UK), Catties, Grains, Gigagrams, Teragrams, Petagrams

Temperature: Conversions to and from Celsius, Fahrenheit, Kelvin, Rankine scale, Delisle scale, Newton scale, Réaumur scale, Rømer scale, Yoctokelvin, Attokelvin, Femtokelvin, Picokelvin, Nanokelvin, Microkelvin, Millikelvin, Kilokelvin, Megakelvin, Gigakelvin, Terakelvin, Petakelvin, Exakelvin, Zettakelvin, Yottakelvin

Speed: Conversions to and from Centimetres per second, Metres per second, Kilometres per hour, Miles per hour, Knots, Feet per second, Feet per minute, Inch per second, Mach, Furlongs per Fortnight, Bubnoff units, Natural units(speed of light)

Power: Conversions to and from Watts, Kilowatts, Horsepower, Ergs per second, Foot-pounds per minute, Decibel-milliwatts, Calories per hour, BTUs per hour, Tons of refrigeration.
Energy: Conversions to and from Electron volts, Joules, Kilojoules, Ergs, Calories, British Thermal Units, Kilowatt hours, Kilocalories, Foot-pounds

Pressure: Conversions to and from Atmospheres, Torrs, Pascals, Kilopascals, Kips per square inch, Pounds per square inch, Feet Sea Water(15° C), Bars, Kilograms per square centimetre, Baryes, Sthenes, Millimetres of mercury
Time: Conversions to and from Nanoseconds, Microseconds, Milliseconds, Jiffies, Seconds, Minutes, Hours, Days, Weeks, Fortnights, Months, Years, Decades, Centuries, Milleniums, Galactic years

Angle: Degrees, Radians, Gradians, Turns, Milliradians, Minutes of arc, Seconds of arc

Data: Bits, Nibbles, Crumbs, Bytes, Kilobits, Kibibits, Megabits, Mebibits, Gigabits, Gibibits, Terabits, Tebibits, Petabits, Pebibits, Exabits, Exbibits, Zetabits, Zebibits, Yottabits, Yobibits, Kilobytes, Kibibytes, Megabytes, Mebibytes, Gigabytes, Gibibytes, Terabytes, Tebibytes, Petabytes, Pebibytes, Exabytes, Exbibytes, Zetabytes, Zebibytes, Yottabytes, Yobibytes

Programmer(Extended from this implementation)
Provides all basic operators like +, -, ×, ÷
Provides logical operators like AND, OR, NOT, NAND, NOR, XOR
Provides operations like left shift(<<) and right shift(>>)
Support for commonly used number systems: Binary, Octal, Decimal and Hexadecimal...