When comparing Toodledo vs Priority Matrix, the Slant community recommends Toodledo for most people. In the question“What are the best cross-platform task apps?” Toodledo is ranked 23rd while Priority Matrix is ranked 47th. The most important reason people chose Toodledo is:
It's possible to create a to-do item by sending or forwarding an email.
Specs
Ranked in these QuestionsQuestion Ranking
Pros

Pro Can create to-do items via email
It's possible to create a to-do item by sending or forwarding an email.
Pro Decent filtering and sorting
Pro Priority organizing
Pro Great GTD implementation
The GTD principles are very perfectly supported by Toodledo.
Pro Functionality-rich
Integrated sharing, note taking, habit tracking, and outlining make this a more powerful tool than a simple list of to-dos.
Pro Upload From CSV
Quickly upload an excel (CSV) file template of tasks to a folder for complex but repeating projects.
Pro Well documented, free-to-use JSON API
If you adopt Toodledo as your productivity system, you can be confident that you can extend it to fit your needs with this programmatic access.
Pro Can tag items
Pro Space to add lengthy text
Notes area that can then be hidden.

Pro Sends a daily email reminder
Toodledo reminds you via email of the tasks on your plate for the day.
Pro Apple Watch support
Integrated support for Apple Watch lets you check on your to-dos on the run.
Pro Helps prioritize, rather than simply listing tasks
Priority Matrix helps me focus on what's truly important on my todo list, so I can work more efficiently.
Pro Super easy to share / delegate tasks
All I have to do is press a button, rather than drafting a whole email to one of my co-workers.
Pro Solid methodology
The software implements time proven methodologies; not just a to-do list.
Pro Lots of different views
Priority Matrix makes it really easy to see your task list in different ways: You can see it in the quadrant view, calendar view, a filterable list, and also a Gantt Chart if you have the business license.
Full disclosure: Originally posted by an Appfluence Intern (who was equally impressed with the software's layout and functionality before working there)
Cons
Con Free version limited to 20 folders
Con Android app has annoying notifications
Whenever the app fails a background sync action for any reason (server issues, lack of internet connection, etc.), a notification appears.
Con Good as a starting point
Toodledo is a good starting point, but is essentially the same as an Excel spreadsheet where you have to build your workflow via the saved searches.
Con Expensive
Used to be free, is now $12+ a month.
