VR, a Railway company in Finland has released their official ticketing app for Windows Phone devices. The highlight is that they are yet to release an iOS and Android app!
Using VR Mobile, you can search for timetables, buy long-distance train tickets and make seat reservations as a multi-ticket holder. You can view your purchase history by logging in to your Veturi account. Using the application, you can also check live train updates, train running information and the services available at stations and their opening hours and contact information.
Download it here from Windows Phone Store for free.