Calculates Trigonometry wrongly

Still this app cannot do trigonometry in DEG mode correctly. What a shame.
Try asin(0.5)
You do not get 30 degree. But some nonsense due to faulty programming.
I already reported the bug but no reaction.
Who is programming this?
Please correct. Its not seriously usable this way.

Veroli65 about CALC Smart Calculator ±, v2.5