After initially using Trello with ‘Scrum for Trello’’ to run our companies Agile process and having to manually create burn downs and release estimates with Excel (after mangling data from the Trello API and a Google Spread sheet) we moved to Trello with GetCorrello (and switched to Kanban after a few months with the teams consent)
Charts from this tool are below. The GetCorrello team were able to add features on demand. Would use them again!
Some samples
Burndown

Cumulative Flow Diagram

Estimated time to complete per label

Control chart

Cycle times

Stats

Slack integration

Our Kanban process
https://www.dropbox.com/s/fj1mr93gqhxv8nc/Fair%20Go%20Kanban%20Process.pptx?dl=0