qt4-default 4:4.8.7+dfsg-20ubuntu2 (arm64 binary) in ubuntu focal

 Qt is a cross-platform C++ application framework. Qt's primary feature
 is its rich set of widgets that provide standard GUI functionality.
 .
 This package sets Qt 4 to be the default Qt version to be used when
 using development binaries like qmake. It provides a default
 configuration for qtchooser, but does not prevent alternative Qt
 installations from being used.
 .
 This package should not be used for building Debian packages. Take a
 look at http://pkg-kde.alioth.debian.org/packagingqtstuff.html for
 more information.