Charging at home will always be the most cost effective and usually convenient way to recharge your vehicle but there will always be times when you need to top up externally. When this happens it always pays dividends to do your homework and plan the night before.
External charge points can become crowded and are regularly left offline/inoperable for months due to technical issues. That’s when apps such as Zap Map become invaluable. As well as giving details of the vast majority of external charge points including location, cost and availability their website also gives a lot of information about the network its statistics.
Some EV’s now have Zap Map functionality built in but if not take a look at their website (and app) to avoid stressful low charge situations in future.