If there are any useful resources not included here, do send a PR.
Please follow the existing format of entries.
Try to keep related resources next to each other.
Keep descriptions short and simple.
Add alternatives to a pre-existing entry using the "Other options: " style, for easy discovery.
Please only add high-quality items to this list. Quality is subjective, but the ideal additions to this list should not be difficult to use or spam the users.
Tools that are free/open-source are preferred. The idea of this list is to provide low-cost yet quality product development tools.