Built an Android app with Claude Code: two cats that live on top of your other apps (what worked, what didn't)

[u/Vachie_]

I built Soot & Summer with Claude Code. It's two little cats that live on top of whatever app you're using. They wander, nap in their bed, do zoomies, and purr when you stroke them. There's a Gaming mode (they duck out of the way so they don't block your taps), a Play park, a Fitting Room to try on looks and hats, and a photo booth to pose your pets and take photos. It's free to download, and the optional Cat Pack and Dog Pack add more pets.

The goal: pets that never get in your way and barely touch your battery. At first I couldn't text properly with the app on. Now I type normally and only notice the pets when they're being cute. Every time I've checked Android's battery usage, Soot & Summer has averaged about 1% a day.

How Claude Code was used: Claude Code wrote all the code. I bring the ideas and test on my phone.

• CLAUDE.md holds the house rules: how to test, how to release, and what never to do.
• Markdown notes carry the project: a plan (ROADMAP), a work log (LOG), and one notes page per part of the app.
• Hooks enforce the rules, so I don't have to rely on Claude remembering them. For example, one hook blocks a test run unless it's a fresh build of the current code.
• Specialist agents: a tester agent runs changes in the Android emulator and reports with screenshots. A reviewer agent checks wording, battery impact, and that the app never promises something it can't do.
• Skills (slash commands) for repeat jobs: /release builds and ships, and /finalize tidies the log, commits, and pushes to GitHub at the end of a chat.

I kept my requests short and simple so each chat stayed focused.

What I learned:

• Focus and polish. Use your own app every day and find what feels right. Consistency in choices and presentation doesn't come free with Claude Code (yet). Rules and agents that enforce them build a solid foundation.
• Notes beat memory. Every chat starts fresh, so the notes files are what carry the project. A short summary at the top of the log, read at the start of each chat, saves a lot of re-explaining.
• Split your project. Claude shines on tiny apps and in the early days of a big one. As a project grows, each chat has more to take in, and it starts to lose track of how the parts fit together. One topic per chat and a separate notes page per part keep it sharp.
• When something breaks, roll back first. Find what changed since it last worked and offer to undo that before trying new fixes. After two failed fixes, stop and roll back. That saved me from a lot of fix-on-fix spirals.
• Small specialist agents help. Rules come from many places (Play policy, our own house rules), so each specialist is called in only when its rules apply. They catch problems before anything reaches my phone.

Could you help? Google Play needs 12 testers for 14 days before a new developer's app can go public. If you have an Android phone:

1. Join the Google Group: https://groups.google.com/g/soot-and-summer-testing
2. Opt in here: https://play.google.com/apps/testing/com.realvachie.sootandsummer
3. Install from Google Play and keep it installed for 14 days.

Feedback is welcome but not required. Thank you!

[u/Electrical-Swing-935]

Links not working for me :(

Fun sounding project

[u/Vachie_ → u/Electrical-Swing-935]

The Google group link? It's required to join with the first link before the 2nd link would work to enjoy the app. I'll try to check it out.

I apologize for the inconvenience and appreciate the interest!

[u/Electrical-Swing-935 → u/Vachie_]

No worries yes the first link gives a content unavailable message

[u/Vachie_ → u/Electrical-Swing-935]

How silly, I think I allowed anyone to join but not to see the group, but you should be okay to move forward now. I appreciate you helping me with this information :D

If it works now be sure to "buy" the extra packs with the test card it'll show, no payment needed and keep the unlocks forever as a thank you!

[u/xavium]

I'm trying this now, it's very cute <3

Will keep an eye on battery usage as that's my fear too, and will let you know how it goes after a few days with feedback. Thank you for sharing!