Per this, Realmac Sofware's Clear to-do list app is currently free for the next 24 hours. This is the first of two 24 hour windows in which the app will be free, giving everybody running Clear+ an opportunity to return back to Clear, which like Clear+ is now a universal app, and is more importantly, Realmac Software's way forward with Clear. Confused? Nevermind that, just go and get the app for free while you can.
Clear by Realmac Software (free today | $4.99) is available for iPhone and iPad