Drawing On Top Of Another Application

[Homogenn]

Im not sure this is not working for you, but at very least, I would get the graphics reference from within the timer and release it when done...

private void timer1_Tick(object sender, EventArgs e)
  {
  using(Graphics eqGraphic = Graphics.FromHwnd(ptr))
  {
    eqGraphic.DrawString("HELLO", font, brush, new PointF(100, 100));
  }
}

I would guess this is not working for you because you dont have the right pointer to create the graphics object, can you make it work first with a known graphics object... like inside a picturebox?

Well, I released the graphic object in the FormClosing event instead, I don't know what's more efficient.

The problem isn't that it doesn't paint it in the window (it does), but that it instantly disappears, thus if I increase the interval number for the timer, the text instantly disappears and reappears at a decreased interval.

I don't know if this is a question for a GDI forum instead, perhaps?