When comparing Casual vs Teuxdeux, the Slant community recommends Teuxdeux for most people. In the question“What are the best cross-platform task apps?” Teuxdeux is ranked 59th while Casual is ranked 67th. The most important reason people chose Teuxdeux is:
On desktop, tasks are assigned to a single line. To see the full description, you can hover over that task. Editing can be done by double clicking, and re-ordering the events are as easy as dragging them around. It also supports markdown - a common web formatting tool that allows italics by putting single asterisk (*) around words or phrases, and bold can be done by using two (**) before and after the phrase you want to be bold. It can also handle links by putting the text you want visible in square brackets, and the link in round brackets so this: \[Slant Homepage](https://www.slant.co] would look like this: [Slant Homepage](https://www.slant.co)
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Tracks task dependencies using a graph
Pro Great to-do templates
Every to-do list & project can be saved as an amazing template that you can re-use in the future.
Pro Offers a high-level overview of projects
The workflow with dependencies shows where the things are at a glance. No more frustrations of how your project is going and who is doing what.
Pro Sync deadlines to Google Calendar
To-do items can be integrated with your day-to-day schedule using Google Calendar.
Pro Visual way of organizing your work
The workflow includes dependencies and shows you where things are at a glance.
Pro Fast, easy to use interface
On desktop, tasks are assigned to a single line. To see the full description, you can hover over that task. Editing can be done by double clicking, and re-ordering the events are as easy as dragging them around.
It also supports markdown - a common web formatting tool that allows italics by putting single asterisk () around words or phrases, and bold can be done by using two (*) before and after the phrase you want to be bold. It can also handle links by putting the text you want visible in square brackets, and the link in round brackets so this: [Slant Homepage](https://www.slant.co] would look like this: Slant Homepage
Pro Very focused, allowing it to be the best at one thing
Instead of trying to be a both a calendar and to-do app, it focuses much more on the to-do aspect. There is a calendar view, however your tasks aren't organized by time - just by order. You can reorder the day's events, and if you don't get them done they will automatically roll over into the next day, so you can be sure that you aren't ever missing anything.
Cons

Con Price
At its cheapest level, Casual is $9 per month for two users and two GB of storage. The trial period is short and there is no free version.
Con Subscription based will cost money each month
Instead of a single time purchase, Teuxdeux costs $3 each month, or $24 for a full year. There is a free 30 day trial, so at least you can try before put any money forwards, but a one time fee - even if it's $10 - is cheaper in the long run than a few dollars each month.
Con No Android support
