question: Identify some of the most innovative mobile app interfaces designed in the past five years. I want a concise summary, not exceeding 120 words. The first word of the second paragraph should be "Innovation."
answer: In recent years, several mobile app interfaces have stood out for their innovation and user-centric design. Notably, the interface of "TikTok" has redefined user engagement with its immersive, full-screen video experience and intuitive swipe navigation. "Clubhouse," with its minimalist audio-chat interface, has pioneered a novel social interaction model. "Notion" has also gained attention for its customizable, modular workspace, allowing users to tailor their productivity environment. Additionally, "Robinhood" transformed the investment experience with its sleek, user-friendly interface, making trading accessible to a new generation.
  
  Innovation in these interfaces revolves around simplicity, personalization, and immersive user experiences, setting new standards in mobile app design. These apps not only enhance functionality but also create engaging, seamless interactions for their users.