What are some alternatives?
When comparing Pixel Pix and TIC-80, you can also consider the following products
Responsive Pixel Art - It's exactly that... responsive pixel art 🙃
PICO-8 - Lua-based fantasy console for making and playing tiny, computer games and programs.
Aseprite - Aseprite is an art program dedicated to the creation of pixel art.
Pixel Vision 8 - 8-bit fantasy console built on top of an open source C# SDK
piCSSel-art - Draw pixel art with CSS!
8bitworkshop - Online IDE for Atari 2600 development based on Javatari.