From what the SoloLearn app Made of.......... Java? or C#???????

Question

From what the SoloLearn app Made of???????
Java - Android Studio or else ???
C# - Xamarin Studio ???
JavaScript - Ionic Framework or else

Answer 1

java for mobile
javascript for front end (web app), i don't know about the back end.

Answer 2

could also be JavaScript with ionic framework

Answer 3

Most probably Java.

Answer 4

i think with java for android and with swift for ios