Here is the list of principles behind the great UI design of Google products:
- Useful: focus on people – their lives, their work, their dreams.
- Fast: every millisecond counts.
- Simple: simplicity is powerful.
- Engaging: engage beginners and attract experts.
- Innovative: dare to be innovative.
- Universal: design for the world.
- Profitable: plan for today’s and tomorrow’s business.
- Beautiful: delight the eye without distracting the mind.
- Trustworthy: be worthy of people’s trust.
- Personable: add a human touch.
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