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I built an app that forces me to drink water before I can open TikTok

I built an app that forces me to drink water before I can open TikTok

by danndecl·Feb 18, 2026·2 points·2 comments
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AI Analysis

●●SolidWizardryCrowd Pleaser
The Take

It turns screen time into a hydration gate: apps stay locked until the phone detects a face, a container, and a drinking gesture for about 15 seconds. Doing all inference on-device and using Apple's Screen Time APIs with no accounts or uploads is the genuinely smart part — it's an unusual, privacy-minded technical prank that actually solves the stated problem. Reliability in varied lighting/angles and easy workarounds will decide whether it's clever or just cute, but the engineering is impressive.

Category
Health
Target Audience

iPhone users who overuse social apps and want a physical habit hack; privacy-conscious mobile users and iOS developers curious about Screen Time + vision tricks

Post Description

I wasn’t trying to reduce screen time but trying to drink more water.

So I built an iPhone app (SwiftUI) that locks selected apps using Apple’s Screen Time APIs. To unlock them, ThirstTrapp activates the front camera and watches for ~15 seconds while I drink.

On-device vision checks for:

- a face - a drinking container (glass/bottle) - and a plausible drinking gesture (container overlapping mouth region over time)

If that sequence is detected for ~15 seconds, the apps unlock for a configurable window (e.g. 2 hours). Then they lock again until the next drink.

It doesn’t try to stop me from scrolling. It just makes hydration the entry fee. And since I'm addicted to scrolling I will actually drink. It’s slightly absurd, but it’s been more effective for me than reminder apps ever were.

All processing happens on-device. No images or video leave the phone or are stored. No account registration or login.

Curious what you think - especially from a technical perspective.

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