PowerBrain 4 is an AI chat and chat AI app for iOS and Android powered by ChatGPT and GPT-4 API. It offers a range of features, including instant answers, task automation, and seamless workflow, all powered by advanced natural language processing technology. The app can be used for various tasks, such as answering questions, automating repetitive tasks, scheduling, research, copywriting, idea generation, and social media management. It is available for both iOS and Android devices and can help increase productivity, automate tasks, save costs, and improve communication. The app also features an AI writing tool that generates high-quality content quickly.