The best replacement for qt is gtk.

The best alternatives to qt are rated as following:
★★★★★  gtk
★★★★  wxwidgets
★★★  qtc
★★  mfc
★★  wpf
★★  liter
★  pt
★  boost
★  visual studio
★  swing
★  gallon
  addin
  javafx
  wx
  cocoa
  gal
  qml
  visual c++
  5 qt kitchen aid mixer
  tkinter
  swt
  xcode
  delphi
  gtkmm
  sdl
  wxwindows
  opengl
  tcl

Your alternative for qt is not listed? Suggest!
Speaking about qt, one probably shouldn't forget about opengl.

Other search terms related to qt and their ratings are:
★★★★★ opengl
★★★ qmake
★★★ c++
★★ gui
★★ qml
★★ opencv
★★ cmake
★ sdl
★ mingw
★ webkit
sfml
code blocks
directx
ogre
gstreamer
You have in mind a companion for qt and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of qt in all years. Click on graph for more.
qt
gtk
wxwidgets