If you come across a bug or you want to request a feature, you can always create an issue here.
Also if you want to contribute with code, you are more than welcome. Check the issues section in Github.
You can also help us by sharing Letterpad on your social networks, making youtube videos, improving the documentation and by using the product itself. Information and ideas should always be free and for this to happen, we are taking care of the server costs and maintenance without any investors. If you would like to donate, you can do so from here.