CustomCalculator

Custom Calculator that can be customized for yourself (choose theme and language font). It has functions such as:
√ - square root;
π - pi number;
. - floating point numbers;
()-parentheses;
123456789 - all digits;
÷×+- - standard operations with numbers;
log() - decimal logarithm;
ln() - natural logarithm;
xʸ - exponentiation;
1/х - exponentiation to -1;
% - percentage of a number;
CЕ - full clean of application history;
C - clear entered formula and result;
⌫ - delete one symbol of the formula.
Implemented saving of calculator history, selected theme and font, and the code is written so that it fits any OS, whether Android, Linux, or Windows.