What are some alternatives?
Canva - Canva makes design simple for everyone. Create designs for Web or print: blog graphics, presentations, Facebook covers, flyers, posters, invitations and so much more.
Invision - Prototyping and collaboration for design teams
PicMonkey - PicMonkey is a feature-rich online photo editor that works right in your browser; no downloads...
Zeplin - Collaboration app for UI designers & frontend developers
Lucidpress - Lucidpress is a web-based design and layout application that enables anyone to create beautiful...
Balsamiq - Balsamiq. Rapid, effective and fun wireframing software.