First of all tank you for using Producteev and for taking time to send us your feedback.
On Producteev we strongly believe that an effective workflow has to be well structured. In order to reach this vision we created a lot of different filters and sorting options to be sure that every users can customize its task list. However to offer customizable ordering on the tasks, and on all the devices, is a real challenge. That would imply to deal with ineffective filters, and to replicate this user-generated order on all the devices.
We already thought about this, and we still believe that it would be useful for some users, but as of today we do not have enough resources to dive into this big task. That may come in the future, but it's not planned to be released at anytime soon.
Thank you for your long answer.
I can understand this … and looking forward to your next updates for more features!