Design an app like Uber for the driverless cars of Google for children below 16 years old.

This question is asking you to conceptualize an app like Uber but specifically tailored for autonomous (driverless) cars operated by Google, with the key demographic being children less than 16 years old. To create an effective solution, you would need to take into account the unique requirements and limitations of this target demographic. Key factors to consider would include safety measures, user interface (UI) design, parental permissions and controls, route optimization, privacy concerns, and adherence to legal regulations pertaining to minors' use of such services.

To design an app like Uber for Google's driverless cars aimed at children below 16 years old, safety and simplicity would be primary considerations.

Firstly, the app would be called "Googo": safe transit for kids. The on-board analytics of Google's cars would be used to ensure that the vehicle operates within set speed limits and strictly follows all traffic regulations. Real-time tracking data would be shared with parents or guardians via the Googo Parent App, where they can monitor their child's journey.

The user interface for the child's app would be colourful and user-friendly, with simple, large icons and minimal text. Beyond selecting a destination, the app will offer high-contrast visuals and a virtual assistant's voice could guide the child through the process.

Further, facial recognition software could be used to ensure that the car only unlocks for recognized, registered children. For additional safety, the vehicle would have an emergency button linked to emergency services and Parent App.

Parental controls would be an essential part of the Googo service. The parent would have the authority to approve the ride request. They could also set "safe zone" geographical boundaries where the child can travel.

Adding to this, AI mechanism would be used to learn, predict, and suggest most frequently used routes with a preference of daylight hours.

By designing "GoGo Kiddo", a ride service for children on Google's self-driving cars, I would focus on safety, accessibility, and engagement.

Safety being of utmost importance, the car itself would only move after biometric verification via fingerprints or facial recognition of the child passenger. Real-time GPS tracking would be available, with location updates sent to the parents at regular intervals. In-app emergency features like an SOS button and direct connection to parents' contact details would be included as well.

A simplified and engaging user interface would make the interaction easier and enjoyable for children. The design would be colourful, vibrantly animated, and would rely heavily on voice prompts to direct users through the process. It can have in-app games or educational interactive activities to keep the child engaged during the ride.

Since the primary users wouldn't have payment options, "GoGo Kiddo" would feature an integrated payment system that's usable by parents from their devices. They would receive any payment prompts, and can control the ride settings, pick up and drop off locations.

Finally, for legality and security, any registration to use the service will require parental approval, ensuring parents have full control over their child's usage. The app would respect privacy laws and not collect any unnecessary data about the users.