Get some of this from halfrauds http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_195717_langId_-1_categoryId_255223 spray it on and wait for it to dry.
I'd be interested to know what the insurance companies have to say!! Would you leave your keys AND your car with an unlicensed bandit!? Stupid is, stupid does.
Used it as a back up in hire vehicles and it seemed ok but haven't used it on a permanent basis at all. Don't know about other Apps but it has a nice feature to run the audio via car speakers over bluetooth.