How to Use Google Gemini’s Nano Banana (Plus My Go-To Prompt Trick!)

Siddharth Madavan
Nov 7
2 min read

Google’s new Gemini Nano Banana might sound funny, but it’s actually a powerful mini AI model built directly into your phone. It’s fast, private, and works even when you’re offline. Here’s a quick guide to understanding it, enabling it, and using it for creative tasks like image generation.

🍌 What Is Gemini Nano Banana?

It’s a lightweight, on-device version of Google’s Gemini AI that gives you:

Faster responses
Better privacy
Offline summaries and smart replies
Quicker voice typing and transcription

Think of it as a tiny AI assistant built inside your device.

📱 How to Enable It

Update your phone:Settings → System → System update
Enable Gemini:Settings → Apps → Gemini → Enable
Turn on On-Device AI:
- Go to Settings → About Phone
- Tap Build Number 7 times
- Open Developer Options
- Enable AICore → Gemini Nano / Nano Banana

That’s it — now your apps can use on-device AI.

✨ My Trick for Better Image Prompts

From my experience, the easiest way to create great image prompts is to let ChatGPT refine them.

My workflow:

I type a rough idea (like “robot in a classroom”).
I ask ChatGPT: “Turn this into a detailed image prompt.”
ChatGPT expands it with style, lighting, colors, and composition.

Then I paste that final prompt into Gemini, DALL·E, or Midjourney.The quality always improves.

✅ Sample Prompts You Can Try

🌱 Simple Prompts

“Cute robot in a colorful classroom.”
“A peaceful night sky with glowing stars.”
“A cozy fall café with warm lights.”

🎨 Improved Prompts

“A friendly cartoon-style robot teaching kids in a bright classroom, sunlight through windows, vibrant colors, animated film look.”
“A futuristic city with neon lights at night, flying cars, cinematic perspective.”
“A cozy café with hanging plants, warm golden lighting, latte art, soft autumn tones.”

🎉 Final Thoughts

Gemini Nano Banana brings powerful AI straight to your phone, and when paired with ChatGPT to refine your prompts, you can create stunning, detailed images with almost no effort. Try the prompts above, customize them, or let ChatGPT enhance your ideas even more.