Is there a possibility to connect external 4G and GPS antenna? The OBDII port is mostly located under the dashboard where there is not a good signal reception. Especially in those type of cars with electrically heated windshield like Ford or new VW.
Welcome to the forum.
Sure its possible to connect an external antenna, but you should not need to. The AutoPi uses both passive and assisted GPS, making sure it will be able to track your position, even if located within your dashboard or if you have a heated windshield.
If you do want to connect an external antenna, you can do so through a U.FL connector, which is standard antenna connector.