diff --git a/go.mod b/go.mod
index acd2e12..5efb099 100644
--- a/go.mod
+++ b/go.mod
@@ -2,4 +2,7 @@ module github.com/vsariola/sointu
 
 go 1.15
 
-require github.com/hajimehoshi/oto v0.6.6
+require (
+	gioui.org v0.0.0-20201106195654-dbc0796d0207
+	github.com/hajimehoshi/oto v0.6.6
+)
diff --git a/go4k/cmd/sointu-tracker/main.go b/go4k/cmd/sointu-tracker/main.go
new file mode 100644
index 0000000..1cc2284
--- /dev/null
+++ b/go4k/cmd/sointu-tracker/main.go
@@ -0,0 +1,24 @@
+package main
+
+import (
+	"fmt"
+	"gioui.org/app"
+	"gioui.org/unit"
+	"github.com/vsariola/sointu/go4k/tracker"
+	"os"
+)
+
+func main() {
+	go func() {
+		w := app.NewWindow(
+			app.Size(unit.Dp(800), unit.Dp(600)),
+			app.Title("Sointu Tracker"),
+		)
+		if err := tracker.New().Run(w); err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+		os.Exit(0)
+	}()
+	app.Main()
+}
diff --git a/go4k/tracker/keyevent.go b/go4k/tracker/keyevent.go
new file mode 100644
index 0000000..d302bef
--- /dev/null
+++ b/go4k/tracker/keyevent.go
@@ -0,0 +1,17 @@
+package tracker
+
+import (
+	"gioui.org/io/key"
+	"os"
+)
+
+// KeyEvent handles incoming key events and returns true if repaint is needed.
+func (t *Tracker) KeyEvent(e key.Event) bool {
+	if e.State == key.Press {
+		switch e.Name {
+		case key.NameEscape:
+			os.Exit(0)
+		}
+	}
+	return false
+}
diff --git a/go4k/tracker/layout.go b/go4k/tracker/layout.go
new file mode 100644
index 0000000..b7ef134
--- /dev/null
+++ b/go4k/tracker/layout.go
@@ -0,0 +1,7 @@
+package tracker
+
+import "gioui.org/layout"
+
+func (t *Tracker) Layout(gtx layout.Context) {
+	t.QuitButton.Layout(gtx)
+}
diff --git a/go4k/tracker/run.go b/go4k/tracker/run.go
new file mode 100644
index 0000000..6e4dab0
--- /dev/null
+++ b/go4k/tracker/run.go
@@ -0,0 +1,35 @@
+package tracker
+
+import (
+	"gioui.org/app"
+	"gioui.org/io/key"
+	"gioui.org/io/system"
+	"gioui.org/layout"
+	"gioui.org/op"
+	"os"
+)
+
+func (t *Tracker) Run(w *app.Window) error {
+	var ops op.Ops
+	for {
+		select {
+		case e := <-w.Events():
+			switch e := e.(type) {
+			case system.DestroyEvent:
+				return e.Err
+			case key.Event:
+				if t.KeyEvent(e) {
+					w.Invalidate()
+				}
+			case system.FrameEvent:
+				gtx := layout.NewContext(&ops, e)
+				if t.QuitButton.Clicked() {
+					os.Exit(0)
+				}
+				t.Layout(gtx)
+				e.Frame(gtx.Ops)
+			}
+		}
+	}
+
+}
diff --git a/go4k/tracker/tracker.go b/go4k/tracker/tracker.go
new file mode 100644
index 0000000..736e680
--- /dev/null
+++ b/go4k/tracker/tracker.go
@@ -0,0 +1,13 @@
+package tracker
+
+import "gioui.org/widget"
+
+type Tracker struct {
+	QuitButton *widget.Clickable
+}
+
+func New() *Tracker {
+	return &Tracker{
+		QuitButton: new(widget.Clickable),
+	}
+}