This app is using to convert amounts from Pound to Carat as well as converting amounts from Carat to Pound.

First of all, let us talk about Pound type and Carat type:


Pound (lb):

Pound, unit of avoirdupois weight, equal to 16 ounces, 7,000 grains, or 0.45359237 kg, and of troy and apothecaries' weight, equal to 12 ounces, 5,760 grains, or 0.3732417216 kg. The Roman ancestor of the modern pound, the libra, is the source of the abbreviation lb.
The pound or pound-mass is a unit of mass used in the imperial, United States customary and other systems of measurement.
Various definitions have been used; the most common today is the international avoirdupois pound, which is legally defined as exactly 0.45359237 kilograms, and which is divided into 16 avoirdupois ounces.
The international standard symbol for the avoirdupois pound is lb; an alternative symbol is lbm (for most pound definitions), # (chiefly in the U.S.), and ℔ or ″̶ (specifically for the apothecaries' pound).



Carat (ct):

The carat (ct) is a unit of mass equal to 200 mg (0.2 g; 0.007055 oz) and is used for measuring gemstones and pearls.
The current definition, sometimes known as the metric carat, was adopted in 1907 at the Fourth General Conference on Weights and Measures, and soon afterwards in many countries around the world.[i]
The carat is divisible into one hundred points of two milligrams each.
Other subdivisions, and slightly different mass values, have been used in the past in different locations.
In terms of diamonds, a paragon is a flawless stone of at least 100 carats (20 g).



By the way, As far as I told, this app is useful for converting amounts from Carat to Pound too usful for converting amounts from Pound to Carat.
So let's start using that.