First I'll try to create a simple todo application that saves all the data to a some database (maria, redis, mongo) and the tasks are managed via REST-service.
Once I've done that I have two ideas what to do after that. I'll either try to create some sort of UI that uses the REST-service or I'll extend the simple todo application to a Kanban board type of application and try to create the UI after that.
I haven't decided with what I'll be creating the UI since I'm not that familiar with current frontend technologies so that'll be decided later.
At first I tried to create a REST-service with spray but that didn't work. Maybe it's just me but to me the spray documentation was incomplete, I also tried out sprays examples from github and had them running via sbt but not with Scala IDE. The examples ran with sbt but when I tried to create my own REST implementation based on the examples the service never responded. Trying to make this simple service to respond to me with no luck for several hours I decided that I'm not going to use spray.
This is still on my todo list but next I'll try create the REST-service with Play 2 hopefully with better results.
Trying to create something with a new language and new libraries can be difficult and in case of Scala and spray it seems to be true. Though this isn't true to all languages, I remember a project where we created a REST-service with Grails with absolutely no experience with Groovy or Grails and that was a walk in the park compared to my experiences so far with Scala and spray.