How to build an App?

Question

Which language can I go for if I want to build an App?

Answer 1

I would say Java is CANCER... but python is LOVE; python is simple and efficient BUT slower than JAVA and C++.

Answer 2

depends on the platform, if you want to make an android app you should go java with android studio, for IOS you shiuld use swift, for web apps yoy need full stack html, for windows phone... meh... forget it.
you could use also something like xamarin to make cross platform apps, the choice is yours