The App access is standard*, the access data are obtained from the dealer.
The communication between vehicle and app works via mobile (2G/3G) and SMS, a SIM card is not needed.
The "App" was a web-based application until the End of 2018 and but has been replaced by a full-fledged app since mid 2018. With it you can check things like the state of charge, the charging process and the "Eco-Score". Amongst other things you can set the time for the pre-air conditioning.
The app will be available till the 31th of December in 2024.
*Only available in selected European countries