If you're a designer type, you've probably heard about Sketch. It's an ambitious attempt (by a team of just four people) to produce a vector drawing application that can make the Adobe Creative Suite a moot point for most designers. That's not their mission statement, but they've created a tool that can do just that. Version 3 of Sketch is out now, and it fixes some rough edges and adds some vital features.
The banner feature for Sketch 3 is "Symbol" support. This is similar to Smart Objects in Photoshop, where you can create and duplicate a set of layers as an object, and modifying any of those objects applies the changes to every instance of it. Sketch 3 lets you easily turn a group of layers into a Symbol, and then re-use it without worrying about how many elements you'll have to update to institute a design-wide font or color change.
I've been using Sketch since version 2 came out, and it actually has replaced Adobe apps for me. Granted, my work is for my own apps and websites these days, so I'm not required to share my files in any common format, and my needs are less particular. Sketch makes generating CSS-friendly graphics, icons and mockups really easy (compared to the learning curve of Illustrator), and the export tools are outstanding for anyone working on web or app design. I won't lie, though, there have been times I thought I could have done something a lot faster in Photoshop than in Sketch.
In version 2, scrolling on the screen was abysmal. It's much improved in version 3, but still not perfect. The redraw sometimes leaves artifacts on the screen and usually requires restarting the app. I don't find the mode-based panel on the right to be consistently intuitive, and often spend time searching for the button that will get it back to the set of options I need. That being said, once you get used to it you stop having to think about things like that.
Sketch on its own is a great tool for anyone working with graphics at any level of experience. What's cool to me is the user community behind it, though. If you try it out, make sure you check out some of the available resources and see what it can actually do. Plugins can be written in JSTalk (from the developer of Acorn, the other half of my Photoshop/Illustrator replacement), and some of the best have been collected on GitHub. It was the actions from bomberstudios that were a turning point in my path to deciding whether I could stick with Sketch or not.
For iOS devs, there are some especially great resources, including the Sketch Mirror app for seeing your designs on iOS devices. There are some great articles out there on workflows so slick they seem magical, and a ton of great resources from sites like Sketch App Sources. Bohemian Coding keeps a pretty good list on their Resources page.
If you've never used Sketch, now's a good time to be a new customer. The app is currently US$49, available on the App Store and off (with free trial available). There's no "upgrade price," per App Store standards (read: shortcomings), so version 2 users have to buy the whole app again. Users who purchased in March or after can email the developers and get a non-MAS license. The $49 price is an intro price, and after this week it's set to go up to $74.99.
Sketch is a powerful, extensible tool for creating production-ready designs and graphics. It still feels a bit like a work in progress sometimes, but it's always come through for me in the end.