The iPhone app has probably seen the biggest set of changes. Todoist says that version 11 has been "almost" completely rewritten from the ground up, but on the surface it'll feel very familiar to anyone who's used the app since version 10 dropped last spring. The first notable change starts on your iPhone's home screen, where 3D Touch has been enabled for the iPhone 6s and 6s Plus. Pressing hard on the app's icon brings up a menu so you can jump right to your one day or seven day task views, or you can just jump right into adding a new item to your list. 3D Touch is also enabled in the app itself for getting a pop-up of any web link attached to a to-do item.
Other changes include the ability to reply to comments on tasks directly from notifications, Spotlight search support, deep-linking so that Todoist links open in the app rather than the Safari browser and a few iPad Pro optimizations including improved keyboard shortcuts. It's not a radical reworking of the app, but 3D Touch support as well as more actionable notifications and integration with the iPhone's native search definitely make it an easier app to use.
Going along with the iOS update is a new Apple Watch app. Perhaps most notable is the fact that this app runs natively on the Apple Watch, so you can leave your phone behind and still check off items on your list -- it'll sync back to your iPhone (and any other platform you use Todoist on) when you reconnect your Watch. You can also add a Todoist complication to certain watch faces that support it. It'll display the next upcoming item on your task list, and tapping on it brings you right into the app (unfortunately, it doesn't bring you to that specific to-do item).
I experienced a number of hiccups getting the Watch app up and running, perhaps due to its pre-release status -- but once installed, it was fast and synced reliably back to my phone. That's about the best you can ask for out of an Apple Watch app at this point, and Todoist's app is probably the best to-do app on the Watch I've used thus far.
That leaves just the Mac platform, which has seen the least number of notable improvements. The big addition to the Mac app is a new "quick add" prompt you can bring up by hitting command-shift-A on your keyboard as long as Todoist is running. From there, you can just type in your task and use natural language to set a due date and it'll get added to your inbox. I haven't quite internalized it and made it second nature, but I'm sure once the keyboard shortcut sticks in my brain I'll be using it to add anything that comes to mind to my project lists.
If you prefer to do everything in your browser and use Safari, Todoist has you covered as well with a new extension. The plug-in brings up a similar quick add prompt as you'll see in the Mac app and also saves whatever web page you're on to the task -- so if you often save pages to your to-do list, this could come in pretty handy. I haven't tried it out yet, but I imagine most people who use the full Mac app will just stick with that rather than use the browser tool.
All the new apps are available today, and they're all free, regardless of what platform you're using. If you're a real power taskmaster, though, you might want to upgrade to Todoist Premium ($29 per year), which adds features like file attachments, location-based reminders, in-app task searching, more robust labels and filters and a host of other improvements. In fact, the basic version feels a bit bare-bones after using Premium, and other free options like Wunderlist just might outdo it. But if you're already a Todoist loyalist, these app updates should keep you firmly in the company's camp.