SplashFlag Tells the Neighbors You’re Ready for a Pool Party
Bert Wagner created SplashFlag to let the other families in the neighborhood know when his kids are having a pool day.
Access to a swimming pool makes hot summer afternoons bearable and pool days are so much more enjoyable with friends. But how do you let friends know that you’re doing some swimming and that they’re welcome to come over? Texting back and forth with a bunch of different people to try to make plans can be a real hassle, when all you really want to say is “hey, we’re swimming if you want to join us.” To solve that problem, Bert Wagner turned to modern technology and built SplashFlag.
Mr. Wagner created SplashFlag to improve the social lives of his children, who like having the other neighborhood kids over when they’re playing in the pool. SplashFlag is a small IoT device that simplifies the communication for those invitations. Each trusted family in the neighborhood gets a SplashFlag device to put in their home. When the Wagner kids are swimming, Mr. Wagner can activate them with a click. Doing so raises physical flags on all of the devices, indicating that the pool is open for group splishing and splashing.
SplashFlag also has a simple LCD screen to display the time the Wagners started swimming and the time at which they expect to stop. That helps to avoid awkward “oh, we were actually just about to call it a day” situations. Mr. Wagner can even set custom messages, such as “we have pizza and you’re welcome to a slice.”
This is all built around a Waveshare ESP32-S3 Nano development board, which connects to the user’s WiFi after they enter their credentials through a self-hosted captive portal. Each device receives text and flag state notifications via MQTT from a Mosquitto broker that is exposed to the custom SplashFlag web server through WebSockets. That web server lets Mr. Wagner update the system status and he can do so from anywhere in the world through CloudFlare Tunnels.
The other hardware in the 3D-printed enclosure includes a 1602 LCD screen (connected through I2C), a micro servo for the flag, and a tactile button. That button is there to let users perform a factory reset for the device. In addition, it lets parents clear the current message and flag status — a clever and considerate inclusion, as parents may not want their kids hassling them about going to the pool every time there is an invitation.
We really like this project, as it is a practical way to foster community and to help kids socialize. Those are both cited as common issues in modern society and SplashFlag is a great step towards reversing the trends.