Octopus

Really helps when you are trying to figure the sitemap of a new projuct – the feature set is perfect for quickly drafting up even complicated hierarchies and allows simple sharing with others.

Learned about this app last night. I'm using the free version, but I will probably upgrade to the Pro because I like how easy it is to create wireframes and sitemaps. It may not be what you want to use for high-budget large websites, but it's great for small and medium size site planning. I especially like the variety of page wireframe page elements it offers. Viewing the elements in a pop-up provides some ideas for what elements can go on a page. I'm looking forward to using the app with my clients.

Great for brainstorming, but simply awesome for the next stage, when the sitemap needs to be more formalized. You'll get enough structure to have control and overview, while still being free enough to move things around and do things "your way". Really easy to use, not overwhelming like other tools can be. The free plan can feel a bit limited, but enough to get started. The pro plan is great, but the price step up to the team plan is a bit steep when you're a small team (1-3 people), I must say.