note Side Hustle: 10,000 Yen a Month with Just a Smartphone—3 Free AI Tools You Can Use During Childcare, Handpicked by a 40-Year Veteran Engineer

The 15 minutes while your child is napping.

What if you could write a note during that time and earn 10,000 yen a month?

Are you thinking, "AI sounds too difficult"?

Don't worry. You can do it all with just your smartphone. And it's all free.

There are actually this many free AI tools available

• Claude—Long-form content, writing quality, article structure

• Gemini—Image generation, Google integration, latest search

• ChatGPT—Versatile, brainstorming, speed

• Perplexity—Real-time search, answers with citations

• Microsoft Copilot—Word/Excel integration, business documents

• DeepSeek—High performance, coding specialized

• GROK—X trends, social media analysis

All have free tiers. All can be used on a smartphone.

It's overwhelming, isn't it?😅

Dan-chan has narrowed it down to 3.

If you're focusing only on a note side hustle, 3 is enough.

For those wondering, "Who is Dan-chan anyway?", click here.

These are the 3 chosen by someone who is a 40-year engineer, has watched 1,000 movies, and has used AI to generate sales for 4 consecutive months using only free AI tools.

1. Claude—Your partner in creating articles together

• App Store: https://apps.apple.com/us/app/claude-by-anthropic/id6473753684

• Google Play:https://play.google.com/store/apps/details?id=com.anthropic.claude

What can it do?

• "I want to write an article like this, can you give me an outline?"

• "Make this text easier to read."

• "Come up with 10 titles."

Just by saying, "I want to write an article like this today," it will generate an outline for you. All you have to do is flesh it out.

② Gemini—Your partner for creating article header images

• App Store:https://apps.apple.com/jp/app/google-gemini/id6477489729

• Google Play:https://play.google.com/store/apps/details?id=com.google.android.apps.bard&hl=ja

What can it do?

• Create article header images for free

• Use without watermarks

• Ready to use immediately if you have a Google account

Just by describing the atmosphere, like "veranda, tea, sunset, warm light," it creates an image. Zero design knowledge required.

note articles are much more likely to be read just by having a header image.

③ ChatGPT—Your partner when you're stuck for ideas

• App Store:https://apps.apple.com/jp/app/chatgpt/id6448311069

• Google Play:https://play.google.com/store/apps/details?id=com.openai.chatgpt&hl=ja

What can it do?

• Brainstorming ideas when you're stuck on 'what should I write today?'

• Instantly generating 10 title candidates

• Suggesting hashtag ideas

Because the responses are fast, they are easy to use for quick tasks.

Answering the concern: 'Are they really free?'

All of them have free tiers.

However, there is a limit to how much you can use per day. If you use too much, it will say 'That's all for today'.

But if you wait, it resets. You'll be able to use it again in a few hours.

That's why you should use all three.

Claude -> Gemini -> ChatGPT -> back to the refreshed Claude.

If you use all three, you effectively have triple the free quota. You'll never run out of time during those 15-minute childcare breaks.

Here is how to use the three tools

• Creating article structures and text -> Claude

• Creating header images -> Gemini

• Brainstorming ideas and titles -> ChatGPT

When one reaches its limit, move to the next. Use three, and you get three times the free quota.

No matter how many 15-minute childcare breaks you get, at least one of these AIs will always be working.

AI Hallucination Concrete Example—The day Claude wrote a lie in an article, the full record of the moment a 40-year veteran engineer spotted it

AI Hallucination Concrete Example Part 2—The day Claude invented a 'non-existent film award,' the full record of the moment a 40-year veteran engineer stopped it

The Pattern for Monetizing note—The full record of the day I made 3,960 yen by asserting data about a movie I hadn't watched

Can you really monetize note without social media? The honest, complete record of a 40-year veteran engineer who tracked data for several months

How to increase note followers—No need for collaborative magazines; I'll tell you everything about the 'Engawa' system where you get featured just by following

How to read the note dashboard—Views, likes, and comments: what these three numbers tell you

note paid article pricing—¥300, ¥500, ¥980, ¥1,980: A 40-year veteran engineer asserts based on data (¥980)

Why did Motoko Kusanagi disappear? The true nature of what Mamoru Oshii kept questioning in 1995, in the 2026 AI era

#noteSideHustle #WorkFromHome #MomSideHustle #FreeAI #AIUtilization #SmartphoneSideHustle #noteMonetization #ParentingMom #Claude #Gemini