I'm building a PHP script which ends up with an array of latitude, longitude pairs (around 2,500), and I want to be able to reverse geocode them into full adresses, then recording them on my database.
But before I start coding I was curious whether the ArcGIS REST API has any restrictions at all: is it free or do I need to subscribe? Do I need an API key? If so, where do I get it? Are there restrictions regarding requests per minute / hour / month? I've looked around their docs, but can't seem to find anything non-technical.