How to properly sort upper and lowercase Strings in Array in Android? [duplicate]

Answer 1

Use a Comparator:

Collections.sort(caps, new Comparator<String>{
    public int compare(String s1, String s2){
        return s1.toLowerCase().compareTo(s2.toLowerCase());
    }
});

Answer 2

Collections.sort(); lets you pass a custom comparator for ordering. For case insensitive ordering String class provides a static final comparator called CASE_INSENSITIVE_ORDER.

So in your case all that's needed is:

Collections.sort(caps, String.CASE_INSENSITIVE_ORDER);