WattsUp is available for both IOS and Android. Well worth having on your phone.
I believe the fee (which will provide additional features) is £0.99 a month.It very useful for telling you how far it is to the nearest charger. Also increasingly it is supporting more charge networks to show live status. I like the route planning showing all chargers along the planned route.
I understand the developer is adding more features and that their may be a small monthly fee in future which I would consider paying for the increase in features and accuracy.