The most impressive thing about this tool is that its free! It's very simple and easy to use and understand. I dislike only the fact that sometimes it takes a while to load everything, but that's not really important. For simple flowchart I recommend this platform. I use it as a quick way to get some ideas without investing a lot of time into drawing diagrams by hand or going to a designer. The ability to create quick wireframes with different options like flow charts or prototypes. It has an interactive tutorial so you don't have to worry about anything at all. I would prefer if there was more room on each card because it's quite small which makes some things difficult to see. You can use this tool to quickly build your wireframe ideas before building them out using other tools such as Photoshop/Sketch etc.