Concentrate is described as 'Mac desktop app that helps you work and study more productively by eliminating distractions'. There are more than 10 alternatives to Concentrate for a variety of platforms, including Mac, Windows, Linux, Android and Google Chrome. The best alternative is LeechBlock, which is both free and Open Source. Other great apps like Concentrate are Freedom (Paid), StayFocusd (Free), FocusMe (Paid) and SelfControl (Free, Open Source).
LeechBlock is a simple free productivity tool designed to block those time-wasting sites that can suck the life out of your working day. All you need to do is specify which sites to block and when to block them.
Freedom is an application that disables networking on an Apple computer for up to eight hours at a time. Freedom will free you from the distractions of the internet, allowing you time to code, write, or create.
SelfControl is a free and open-source application for Mac OS X that lets you block your own access to distracting websites, your mail servers, or anything else on the Internet. Just set a period of time to block for, add sites to your blacklist, and click "Start.
Focus is a Mac app that blocks distracting websites (like Facebook and Reddit) and applications, so you can improve your productivity. It has lots of awesome features like scheduling, showing motivational quotes on blocked pages, whitelisting and pomodoro support.
Too many windows to manage? Big display? Or getting lost in multiple monitors? HazeOver is for you! ? TRIAL version: HazeOver.com Get rid of distractions and focus on your current task. HazeOver automatically highlights the front app window by dimming all background windows.