I've been using Trello for the past year and I love it just as much as anyone else.
It's not a perfect app by any stretch, at least not for my needs, but it's better than anything out there.
I like that it can serve multiple purposes: a to do list and a notepad.
There's a couple things missing though that I'm hoping sharing with this community could maybe help:
1) I would LOVE to see the ability to make boards hierarchical, or stacked, to somehow create "subboards". I cut together this example of what I'm talking about using one of my own boards: https://ibb.co/fxTX1vB
There are Powerups out there that attempt to "nest" boards into other boards, but something like this would be much more visually effective I think. The example I created only shows one level of subboards, but in a perfect world you'd be able to make any amount of subboards simply by dragging a board under another one, which would then nest it underneath.
2) I'd also love to see due dates that aren't locked into a day/time. This ones very specific to me, as I said above Trello doesn't meet ALL of my needs and this would go a long way towards that. The perfect app for me would serve as not only a to do list and a notepad, but also a calendar. I know there are calendar powerups, but they're not effective. First of all, the printing options are unsatisfactory. Second of all, and more importantly, when I'm building a calendar sometimes milestones take place over the course of more than one day. I know Trello is not meant to serve as a calendar, but it would really put it over the edge for me to be able to do this.