Improved change of integer base

[Tugdual]

I support your suggestion and wouldn't mind if we need to keep the twitter format as long as it is simpler to convert.

Also I would expect the same kind of simplification for common units of measurement. Common units are m/inch (I think there is nothing like meters in IP), cm/inch, km/miles, °F/°C, kg/pounds.
Note: if we are to use buttons on screen (and not real calculator buttons) it would make sense to have contextual units of measurement. For exemple if there is a value in cm on stack, we shall see a 'inch' button. Then when you press that 'inch' button, the value is converted into inches but you see the former button replaced by a new 'cm' one. See the idea?

Finally why not having support for currencies?