I Built a Single HTML File App to Teach My Kids About Investing

"What comes with the milk, leaves with the soul" — Russian proverb.

This project introduces D-investments, an app designed to encourage children to invest. This is how the D-investments app icon will appear on your phone.

One crucial skill that traditional education, even through high school, often overlooks is personal finance management.

With my eldest son's birthday approaching, we encouraged him to request monetary gifts instead of physical ones. This allowed him to accumulate a respectable sum for his inaugural investment journey. I explained to my children that investing is akin to a 'magic box' that generates more money over time. To make this abstract concept more visual and interactive, I decided to build a simple app that would allow them to watch their investments grow daily.

From Idea to App

Initially, I considered a physical piggy bank equipped with a display to show the accumulated savings. However, this approach blurred the lines between saving and investing, and also necessitated additional hardware purchases. I sought a quicker, more cost-effective solution: repurposing an old smartphone and developing a straightforward app using basic HTML. This endeavor led to the creation of D-investments, a name blending 'Diversions' with 'Investments'.

How It Works

The app itself is a single HTML file, designed to be installed on a smartphone as a Progressive Web App (PWA). The designated phone is mounted on the fridge, serving as a dynamic dashboard where my children can observe their 'money' appreciating daily. I serve as their 'investment agent,' assigning realistic interest rates – calibrated to be sufficiently motivating while still reflecting real-world financial dynamics.

Configuration Screen

The app features a configuration screen where users can input:

• The children’s names
• The initial invested amount
• The interest rate
• The investment start date

Configuration screen

Using this data, the app automatically calculates and presents:

• Daily gain
• Weekly gain
• Monthly gain
• Total updated balance

Dashboard view installed on the fridge, illustrating daily growth.

Materials Used

• An old smartphone
• A suction mount for attaching it to the fridge

An affordable phone mount, priced at $0.90 on AliExpress.

• The D-investments app, in HTML format

D-investments displaying daily capital growth.

Installation

The installation process is remarkably simple: users just need to open the app's dedicated link on a smartphone and tap the 'Install' prompt from their browser. Afterward, it operates fluidly, akin to a native application.

Final Reflection

The primary objective was not merely to instill the value of money in my children, but to visually demonstrate how investment and time collaborate as powerful allies. Each day, as they observe their modest fund expanding, they begin to comprehend the magic of compound interest – a profound lesson I believe will remain with them far beyond any material gift.

Interested in commenting on or improving the app? Feel free to contact me at: @roberdam