PaletteBrain is a productivity tool for Mac users that offers customizable templates and integrates with various applications to streamline workflow. It allows users to access OpenAI's GPT capabilities, improving their writing and coding skills by providing faster responses to questions. PaletteBrain offers a one-time purchase option for lifetime usage, with pricing plans ranging from standard (for single device use) to enterprise (for unlimited devices). The tool can be used by individuals or small teams looking for an efficient way of completing tasks.