Hi guys,
The
Navigo Découverte card is purchased without application, on the spot at a ticket window. At the moment there's no way to purchase it from abroad, although you can purchase it at any time (e.g. Saturday when you arrive), charged or uncharged with a Carte Orange week/month pass. In the past I've purchased the card, without any Carte Orange on it, weeks in advance for friends who are planning a visit. Unfortunately, you can only do this in person. RATP/STIF doesn't offer any way for visitors do this ahead of their arrival.
The only thing you'll need is a 3.5x2.5cm face photo (smaller than wallet size) to use on the identification card that comes with the Navigo Découverte. As long as you have a photo, the ticket seller will be happy to sell you a card and load whatever type of
Carte Orange week/month pass you'd like. Then you attach the photo onto the paper ID card, print your name, seal it and from that point on, your smart card is valid for use.
Ben