Answer to Prashant:
The iPhone was 5 centimeters to the plane while triing to connect.
Bluetooth was turned on :)) ans the icon turned to white when the plane was turned on.
The bueetooth menu said: "connected to smartplane".
The LED blink two short stroke.
The plane considered  to be fully connected to my iphone but the App did not want to connect to the plane.
I have tried pressing the two fingers but the engine did not want to start.
The problem has been resolved erasing all my network settings on my phone: I Hope I won't have to do it again... :((
Nicolas

Problem solved using "Settings>general>reset>network settings" on my iphone.

Still have the problem... Please help!