Canvas and Gems

Gemini gives you three useful tools for building. Canvas creates apps you can preview and share. Gems are custom helpers that remember their job. Deep Research gathers facts before you build.

What are Canvas and Gems?

Imagine a workshop. Canvas is the workbench, where things get built. A Gem is a trained assistant who already knows how you like things done. Deep Research is the trip to the library before you start.

Building an app with Canvas

Gemini Canvas works much like ChatGPT's. Gemini writes the code in a panel beside the chat and shows a preview you can click. You test, ask for changes, and test again.

Start a new chat at gemini.google.com and pick Canvas from the tools menu. If you can't find it, start your prompt with "Open canvas".

For example, imagine a trip planner. The user enters a destination, dates, budget, and interests. The app writes a day-by-day plan.

Open canvas. Build a web app called "Trip Planner" that I can preview here. I don't know how to code.

Inputs:
- Destination (text)
- Number of days (1 to 7)
- Budget: Low, Medium, or High
- Interests as checkboxes: Food, History, Nature, Art

When I click "Plan my trip":
- Use Gemini inside the app to write a day-by-day itinerary.
- One card per day, with Morning, Afternoon, and Evening.
- Do not state exact prices or opening hours.

Always show this note under the plan: "Check opening hours, prices, and bookings on official websites before you go."
If the destination is empty, show a friendly message instead.
Design: bright and friendly, works well on a phone.

Let's break this down:

• "Use Gemini inside the app" asks for an AI-powered app, one that asks Gemini for a fresh answer each time.
• The rule about prices and hours is a guardrail: a limit that reduces made-up details.
• The reminder note is fixed text, so it shows every time, no matter what the AI writes.

Checking what the AI writes

AI can invent places, dates, or details that sound real. Pick one result and check it yourself. Does each place exist? Is it open on that day? Are the places close together?

If you find a mistake, use it to improve the app's instructions:

The plan put a museum on a day it's usually closed. Update the app's instructions so the AI adds "check if open on this day" next to every attraction. Keep everything else the same.

Fixing and sharing

When you're happy, look for the Share button at the top of Canvas. It creates a link others can open. Test the link in a private browser window first.

Making a Gem

A Gem is a custom version of Gemini with saved instructions. It's like a coworker you've already briefed. Every time you open the Gem, it already knows its job.

Create one from the sidebar (look for Gems or "Explore Gems"). Give it a name, write the instructions, and save it. You can also add files for it to use as reference.

You are a friendly app-planning helper for beginners.
When I describe an app idea, reply with:
1. A one-sentence summary
2. Inputs and outputs
3. 3-4 must-have features
4. A ready-to-paste Canvas build prompt
Keep answers short and in plain English.

Let's break this down:

• The first line gives the Gem a role.
• The numbered list fixes the shape of every answer.
• The last step hands you a prompt you can paste straight into Canvas.

Researching first with Deep Research

Deep Research is like sending a research assistant to the library. You ask a question. It makes a plan, searches many web pages, and writes a report with links to its sources. It takes minutes, not seconds.

Deep Research: What features do popular [type of app] apps have? List the most common features, what users like, and what they complain about.

• Gemini usually shows its research plan first. You can edit it, then start.
• Open a few of the source links to check them.
• You can turn a finished report into other formats, like a web page, from the report's options.

Common mistakes

Skipping the fact check

Wrong: The preview looks great, so the content must be right.
Right: Check a sample result against official sources.

Removing the safety note

Wrong: Make it cleaner by removing the note at the bottom.
Right: Make the note smaller and gray, but keep it visible.

• Using Deep Research for quick facts. Just ask normally.
• Writing vague Gem instructions. Say the role, the steps, and the format.
• Asking for many Canvas changes in one prompt.

What's next?

You've now seen how to build with all three AI chat tools. Next, you'll compare ChatGPT, Claude, and Gemini side by side and learn how to choose between them.