Trello it's a great tool to keep you or your small team work organized, with a simple and minimalist interface, but highly configurable, specially if you have Premium Account. Organize cards by colors to represent priorities and represent groups can be a great way to have a simple board to use Agile, like my case. Also, the plugin for Slack is a great feature.
For first time users, Trello is not very easy to get used to and for you to have the "perfect board", it needs some time to customize. Deadlines of cards isn't what you expect, if you compare to JIRA.
Trello is helping to keep track of simple tasks in small teams. With the notifications and integration with Slack and comment features, it's a gret way of you and your team share your work progress.