Remix is described as 'Ethereum tools for the web' and is an website in the Bitcoin & Cryptocurrency category. There are five alternatives to Remix, not only websites but also apps for Mac, Windows, Linux and Ethereum. The best alternative is Ethereum, which is both free and Open Source. Other great sites and apps similar to Remix are Solidity (Free, Open Source), Bytom (Free, Open Source), KIN (Free) and TokenMint (Paid, Open Source).
Kin is a cryptocurrency and a way to engage, grow, and monetize your digital community. With only so much of it, Kin becomes more valuable as more people spend it. So you get paid when your apps' users spend Kin, letting you make money while also improving user experience.