I've been a fanatical Toodledo user for over 10 years, but since moving from a PC to the Mac I've now moved fully onto Apple Reminders and of course that means using Goodtask 
After using both systems in parallel for a week I'm preparing to move fully to Goodtask and I've some issues to bring up plus suggestions
The issues I have noted on the Mac are:
- Even though the time delay for the task to be checked off has been set to 'None' it can take 3-4 seconds for a task to be checked off.
- Occasionally when changing the list colour the coloured blob next to the list does not change until the app is quit and reloaded
- It is not possible to delete a list from within the Goodtask app, you get an error message. The only way of deleting a list is by going into the Apple Reminders App and doing it in there.
The issues I have noted on the Apple Watch are:
- When changing lists from one to another it can take up to 20 seconds for the correct list to become visible, it seems at first as if the change has not been recognised but it does most of the time eventually take place. On one occasion I had to force close the applet to get the change to be recognised.
- When checking of the last item on a list it appears to flicker and reappear which makes you want to check it of again. If you do check it off again (and it's a repeat daily task) then the task is actually checked off for two days instead of one.
Back to the Mac - UX changes and suggestions. Some aspects may apply to the iOS version of the app too. These thoughts are shared to hopefully help improve (the already great) interface and are from my experience as a front end design engineer. Here we go:
- Sorting options - To me these are unclear in how they work and the sorting dialogue should allow one to set a top level to group on (i.e. date as can be achieved now) and then below that three dialogue boxes allowing the user to have free selection of which fields to sort on. This would make it a lot clearer to configure and add flexibility to the users requirements. As an example I'd want to group on date, then sort on date, priority, and lastly subject.
- Toggle option - show a task count in the daily header divider
- Toggle option - Set whether a pull down operation while viewing a list either activates search (as it is now) or forces a cloud refresh of data. If not have another method of forcing a refresh of data.
- A long standing request - have the option of adding a new divider on to the lists. Many times I've wanted a new divider to separate various sections of a list and it is awkward that the only method of doing this is creating a new list and then deleting it afterwards.
- When looking to add a task or tasks it'd be a great time saver to have shortcut keys for the 'More' and 'Done' buttons so that one can select the buttons instead of via a trackpad click.
- Make the task entry dialog bigger so that it includes a full calendar month selector (possibly with Today and Tomorrow buttons underneath it), this would allow the users to set a date when first adding the task instead of waiting for it to be entered and then changed.
- Pinning of lists - this would be a cool factor. Build in the pinning of lists (like Apple Notes) so that the user can have multiple lists open at one time. This again would massively improve working efficiency.
- Reduce white space in a list. At the moment a standard list has a lot of white space it in which either means the user has to scroll a lot or have a 'long window' open on screen. The view could be improved by eliminating that second line of small text via:
a) Move the list category, due date and priority to the right hand side of the line containing the task. This would also allow such things as the priority to have greater visibility.
b) Make the checkbox we have now multi-functional so that it shows a circular arrow if it is a repeat task and the standard checkbox if it is not.
c) if the above were completed then reduce the white space between the task lines and possibly add a grey dividing line between the tasks.
Possibly a lot of suggestions there but I think if you could consider them then it'd improve the operation of the application and make the list interface a lot cleaner.
No criticisms are intended as a think Goodtask is superb, I just want to help make it even better
Look forward to your thoughts.