Designing a Kids' App With No Ads, Purchases or Internet

At 7am, a parent hands over a phone in the back seat. The child taps an egg. There is no signal, nobody remembers an account password, and the parent does not want a purchase prompt appearing halfway through the drive.

That situation shaped Mochi Hatch, the pet game we built for children aged 4 to 10. The child can hatch one of eight pets, care for it, play five mini-games, decorate a room and grow a garden. The harder design work sits around those activities: the game has no ads, no in-app purchases, no account and no internet access.

Removing those things did not leave us with a normal game minus four features. It changed the structure of the product. We had to decide how play would continue without paid shortcuts, how a young child would understand each screen without much reading, and how a parent could verify the privacy promise instead of simply trusting our copy.

Start with what the app is not allowed to do

Product teams often begin with a feature list. For this game, we also wrote a refusal list.

Mochi Hatch would not show advertising. It would not sell coins, stars, outfits or eggs. It would not ask for an account. It would not contain links that lead a child out of the app. On Android, it would request no permissions at all, including internet access.

These are connected decisions. An ad-supported game needs an advertising system and a network route. A purchase needs store flows, prices and recovery rules. An account needs identifiers and a data service. An external link creates a path from the child's play space to somewhere we do not control.

We chose a smaller boundary: the game runs on the device, saves progress on the device and keeps the child inside the game. The Mochi Hatch privacy policy spells that out in concrete terms, including what is saved and what happens when the app is uninstalled.

That boundary also gives the team a useful test. If a proposed feature needs a permission, an external service or a real-money transaction, it is not a small addition. It changes the product promise and needs to be judged that way.

Replace payment pressure with a complete play loop

Once real-money purchases are removed, the in-game economy has to stand on its own.

Mochi Hatch uses pretend coins and stars. Children earn them by playing, then spend the coins on food, furniture and outfits. They cannot buy the currency, exchange it or convert it into anything outside the game. The terms of use make that limit explicit rather than hiding it in store copy.

This affected how we balanced rewards. A locked item cannot quietly mean “ask an adult to pay”. It has to mean “keep playing”. The five mini-games, pet-care actions, garden and sticker book all feed a loop the child can complete without reaching a checkout screen.

We also removed losing as a source of pressure. There is no timer and no way to lose. A pet recovers quickly, and a crop does not die if the child leaves the game for a week. Those choices make the game gentler, but they also solve a practical interface problem: a four-year-old does not need to interpret a failure state, find a reset control or ask an adult to repair a mistake.

Make every important action readable without a paragraph

Mochi Hatch is designed for ages 4 to 10, and no reading is required for the main play. That rule changes screen design.

The home screen uses large one-tap actions for feeding, bathing and playing. The egg screen asks for one clear action. Pet care uses direct movement, such as dragging a snack to the pet, rather than a menu of written instructions. Language settings sit behind a parent gate because changing the language is an adult decision, not part of the play loop.

We still support seven languages: English, Simplified Chinese, Traditional Chinese, Malay, Japanese, Korean and Spanish. But translation is not a substitute for a clear action. If the child must read a sentence before every tap, the interface has already excluded the youngest part of its intended audience.

This is one reason we build our own products as well as mobile apps for clients. A requirement such as “easy for children” is too vague to test. “The main activity can be completed with one-tap controls and no reading” gives the designer and developer something they can actually check.

Put the privacy promise in the Android build

“Child-friendly” is weak if it only describes colours and characters. A parent also needs to know what the app can collect and where information can go.

Mochi Hatch has no sign-up, analytics, tracking, crash reporting, third-party SDKs or social media integration. Its Android build declares zero permissions, including no internet permission. The operating system therefore prevents the app from making a network connection.

That claim is checkable on the phone. A parent can open Android Settings, go to Apps, choose Mochi Hatch and inspect Permissions. The list is empty.

We prefer this to asking a parent to trust a broad privacy label. The product page can say the game is offline, but the empty permission list is stronger evidence. It also keeps future development honest. Adding analytics later would not be a silent dashboard change; it would require changing the build, the privacy policy and the promise made to parents.

Say what local-only progress costs

No account and no server means Cortex Solution does not hold a copy of a child's progress. Mochi Hatch saves the pets, room, garden, level and settings to one file in the app's private storage on the device.

That is good for data minimisation, but it creates a hard limit: there is no cloud sync or backup. If the app is uninstalled, or the device is lost or reset, the progress is gone and we cannot restore it.

We did not want to bury that trade-off. Privacy copy becomes misleading when it celebrates what is not collected but avoids saying what support can no longer recover. The same issue appears in other accountless apps we have built, which we covered in our local-first app article.

For Mochi Hatch, local-only progress fits the product better than an account system. That does not make it free of consequences. It means the consequence is understandable: the game stays on one device, and so does its save file.

Test the quiet parts, not only the mini-games

The obvious test is whether each mini-game works. The more revealing checks sit around it.

• Start the game with airplane mode on.
• Move through the main play without reading instructions.
• Try every route out of the app and confirm there is none.
• Inspect Android permissions on the installed build.
• Leave the garden alone, return later and confirm the crop waited.
• Spend all available pretend coins and confirm no purchase route appears.
• Uninstall the app and confirm the local progress is removed.
• Open the language setting and confirm the parent gate appears.

These checks turn the promises into acceptance criteria. “No internet” means the game still works in airplane mode and has no internet permission. “No purchases” means an empty balance never turns into a store prompt. “Made for small hands” means the child can recover from a wrong tap without an adult repairing the session.

If you are planning a children's app through our custom software service, write the forbidden behaviours beside the wanted features. They often reveal more about the architecture than the screen list does.

FAQ

Does Mochi Hatch contain ads or in-app purchases?

No. It contains no advertising and no real-money transactions. Its coins and stars are earned through play and cannot be bought.

Does Mochi Hatch need an internet connection?

No. The game is fully offline. On Android it requests no permissions, including internet access.

Does Cortex Solution collect a child's data through the game?

No. Mochi Hatch has no account, analytics or tracking. Progress stays in the app's private storage on the device.

Can lost progress be restored?

No. There is no cloud backup or server copy. Uninstalling the app, losing the device or resetting it removes the only save we could otherwise use.

Planning an app for children and want the safety rules designed into the product from the start? Book a free consultation with Cortex Solution.