For just over two years now I've been using Todoist as my primary to-do list manager and personal organizer software. I pay for the upgraded Premium version at US$28.99/year. I really like it and it's helped me stay on top of all the things I want to get done in my professional life, personal life, local community and beyond.
(Before Todoist, I'd been using Taskpaper and loved the simplicity of its interface and file storage. The software hit a period of being unmaintained and I really needed something up to date, so I switched. Taskpaper has since seen new life as a project, it's worth checking it out again too.)
The Todoist website linked above already showcases many of its features so I won't bother repeating those, but here are a few of the things I especially appreciate:
- The software looks and works the same across the Mac desktop app, the in-browser app, and the iOS mobile app. Syncing is seamless and fast.
- Todoist does one thing really well and doesn't try to do much else. The interface is simple but there's a lot of "advanced" functionality available when you want it. A task can look like just a task, but if you want it can be a task with priorities, recurring due dates on complex schedules, geo-locational reminders, links to related email messages, attachments and voice memos, and more.
- The natural language processing for parsing out date/time settings is really good. I can quickly add a new task that is filed into the right "project" with the right labels, due on just the right day and with a reminder set for when I need it, all by typing one line of text.
- I can get a private calendar feed of my Todoist tasks, so I can see what's coming up on my list in the context of all my other appointments and events.
- You can export lists of tasks in a given project as a template for others to import, or to re-use across multiple instances of the same project. (For example, you could create a packing list template, load it into a new "project" for your upcoming trip to France, and then share it with a Todoist-using friend who's going with you.)
- You can share projects and their tasks with other Todoist users, so that you can assign items to individuals and have everyone see when an item is updated or completed. (So far I have not convinced my wife to do this, but think of the possibilities for jointly maintaining a grocery list!!)
- The API is really powerful, allowing me to integrate Todoist with other software in my life for even more convenience and clarity.
I'll give you an example of that last feature in use.
I have a PO Box at my local post office, and the USPS offers a service where they'll send you an email message when new postal mail is about to be delivered to your PO Box. I have my email account set up to process those incoming messages and call a webhook at IFTTT, where in turn I have an IFTTT recipe set up to create a new Todoist task reminding me to check the PO Box the next time I'm out running errands, with a due date of tomorrow. I don't have to worry about checking the PO Box regularly, and something that might otherwise have been an email that I had to see, read and manually convert to a to-do item is automatically handled for me, keeping my inbox clear.
Another, though perhaps less useful, example is that I created a simple script to query the Todoist API once per day and Tweet out how many tasks I completed the day before:
I completed 5 tasks from my todo list on Mar 5th.
— JCH Things (@JCHthings) March 6, 2017
If you don't already have a task management system you love, I highly recommend checking out Todoist.
N.B. The screenshot shown at the top of this post is a stock image from the Todoist folks; I am not presently signing up for a 5K or going to New Zealand, but I should definitely call my mom soon.
I use Todoist myself and can second your recommendation.
I only use it for personal management at the moment but find it incredibly useful at making sure I don't forget about all the little things that need doing around the house.