I like to know the availability of Windows phone app
Unfortunately, it's not available yet, but we'll consider developing an app for this platform in the future. You're welcome to vote for this request in our Votebox: http://todoist.com/Vote/showProposal/558/
Download it on: http://www.windowsphone.com/pt-br/store/app/metroist/dc8d3a13-de05-46ec-90c5-e1996abaa81b
Give feedback to us! We need this to get better.