Software Ideas Modeler is a free-for-personal-use tool for creating a host of diagram types: use case, class, sequence, state machine, entity relationships, data flow, user interface and so on. And even if you're not a developer you'll be able to create flowcharts, mind maps, Venn diagrams and more.
At first, the program looks much like the competition. Choose your diagram type, and a palette of shapes and drawing options appears on the left. Double-click or drag and drop one of these onto the page, and you can customise its text, background colour, line style and so on. It's all very familiar.
But Software Ideas Modeler goes much further. Check the Properties dialog of a shape, say, and the Style box provides another 30+ ways to customise the look of that object. And you're able to customise it further with tags, rich text notes, a list of other interested users, and much more.
Maybe you're tired of the constant switching between keyboard and mouse in most diagrammers? Software Ideas Modeler allows you to choose your next symbol with one hotkey, its position with another, and automatically adds a connecting line. You're able to build complex diagrams without ever taking your fingers off the keyboard.
There are various smart tools to help. Click any symbol and a floating toolbar appears underneath with a context-sensitive list of symbols which might come next. Click one of these and it's immediately added, with a connecting arrow, leaving the focus on its name. Type whatever text you need for the second box, choose another from its floating toolbar (you don't even have to press Enter) and that's also added. Again, no lengthy mouse movements or drag and drops required.
If you do choose to build diagrams manually then a host of layout options helps to keep them looking good. Drag a symbol onto the page and alignment guides show you where to line it up with everything else. There are tools to move, resize, rotate, align and generally rearrange selected images however you like. You even get various "Auto Layout" options to reorganise an entire diagram in various ways.
You also get layers, group and ungroup tools, a tabbed interface, multiple views on your current diagrams and an array of configuration options. And when you're done, the final diagram may be exported as an image or PDF file, ready for sharing with others.
This all works for us, but if you're using the program commercially, or need more, then the licensed versions are more powerful still. Software Ideas Modeler Professional ($101) alone gets you BPMN and SysML diagrams. matrices, source code generation, reverse engineering, filters, and a whole lot more.
Version 7.61 is a bug fix release.