Steven Schoen's Put.io for Android
This Android app was created by Steven Schoen. You can manage your files, stream and download your videos and start new transfers from the app. It supports Chromecast too! You can find it here.
You can check out Steven Schoen's Google Plus community if you'd like to ask a question or get help with something.
Client for Put.io from Vego Labs
This app, from Sri Lanka, lets you do most of the things that you can do with Put.io, including downloading your files, adding new transfers and casting to Chromecast. You can find it here.