diff --git a/trezorlib/pinmatrix.py b/trezorlib/pinmatrix.py
new file mode 100644
index 0000000000..1ae17f505e
--- /dev/null
+++ b/trezorlib/pinmatrix.py
@@ -0,0 +1,73 @@
+import sys
+from PyQt4.Qt import QApplication, QWidget, QGridLayout, QVBoxLayout
+from PyQt4.QtGui import QPushButton, QLineEdit, QSizePolicy
+from PyQt4.QtCore import QObject, SIGNAL
+
+class PinButton(QPushButton):
+    def __init__(self, password, encoded_value):
+        super(PinButton, self).__init__()
+        self.password = password
+        self.encoded_value = encoded_value
+
+        QObject.connect(self, SIGNAL('clicked()'), self._pressed)
+
+    def _pressed(self):
+        self.password.setText(self.password.text() + str(self.encoded_value))
+        self.password.setFocus()
+
+class PinMatrixWidget(QWidget):
+    '''
+        Displays widget with nine blank buttons and password box.
+        Encodes button clicks into sequence of numbers for passing
+        into PinAck messages of Trezor.
+    '''
+    def __init__(self, parent=None):
+        super(PinMatrixWidget, self).__init__(parent)
+        
+        self.buttons = []
+
+        self.password = QLineEdit()
+        self.password.setEchoMode(QLineEdit.Password)
+
+        grid = QGridLayout()
+        grid.setSpacing(0)
+        for x in range(9):
+            button = PinButton(self.password, x + 1)
+            button.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)
+            self.buttons.append(button)
+            grid.addWidget(button, x / 3, x % 3)
+
+        vbox = QVBoxLayout()
+        vbox.addLayout(grid)
+        vbox.addWidget(self.password)
+
+        self.setLayout(vbox)
+        self.move(300, 150)
+
+    def get_value(self):
+        return self.password.text()
+
+if __name__ == '__main__':
+    '''
+        Demo application showing PinMatrix widget in action
+    '''
+    a = QApplication(sys.argv)
+
+    matrix = PinMatrixWidget()
+
+    def clicked():
+        print "PinMatrix value is", matrix.get_value()
+        sys.exit()
+
+    ok = QPushButton('OK')
+    QObject.connect(ok, SIGNAL('clicked()'), clicked)
+
+    vbox = QVBoxLayout()
+    vbox.addWidget(matrix)
+    vbox.addWidget(ok)
+
+    w = QWidget()
+    w.setLayout(vbox)
+    w.show()
+
+    a.exec_()