Jira - Best for complex rollouts
Jira is a project management software that is particularly useful for managing complex projects such as Salesforce rollouts. Jira enables project managers to break down the project into smaller, manageable tasks, and track their progress using agile methodologies.
Jira is considered an industry-standard for Enterprises due to its robust feature-set and security preferences.
The amount of features Jira has could be overkill for a startup, but if you're managing a complex rollout that requires documentation as well, consider Jira and it's companion knowledge base product, Confluence. Jira provides project managers with features such as task management, reporting, and real-time collaboration, making it easier to manage a large team of developers, administrators, and other stakeholders. Jira is a popular choice for organizations that follow agile methodologies and require a flexible and scalable project management solution.

Trello - Easiest to Use
Trello is a visual project management software that can be used to manage a Salesforce rollout project effectively. Trello enables project managers to create boards, lists, and cards to track the progress of their project.
Trello, unlike Jira, is notoriously simple in format - just
a kanban board with cards. Trello is so fun and easy-to-use that Atlassian, the marker of Jira,
acquired them in 2017.
If you like keeping things simple and want to keep your rollout simple too, Trello is the tool for you.
Trello also provides features such as checklists, due dates, and attachments, making it easier to manage tasks and collaborate with team members. Trello is a great choice for organizations that prefer a simple and intuitive project management software solution.