Per-hour app scroll limits, not daily caps

What to build

A mobile app-blocker for iOS or Android that lets users set per-hour (rolling-window) limits per app — e.g. 10 minutes of Reddit per hour — instead of only a flat daily cap, aimed at people already using Screen Time, Opal, or One Sec who find daily limits too blunt.

Flat daily screen-time caps let people binge for hours before hitting the ceiling; a tool that enforces per-hour or rolling limits per app would close that gap for users of existing blockers.

Demand

People who already install screen-time/blocking apps (Screen Time, Opal, One Sec) are self-selected quitters who want tighter control over binge windows, not just a daily total — the request is for more granularity, not a new habit.

• r/nocode (Reddit)Feature request

  User post: 'Screen time limits would be so much more useful if you could set a per hour scroll limit (e.g., 10 min of Reddit per hour)' instead of one big daily limit.

• Opportunity descriptionAnalysis

  Analysis frames existing Screen Time, Opal, and One Sec users as the target market because they 'find daily caps too blunt,' pointing to a granularity gap in current tools.

Stack

• Apple Screen Time API (Family Controls, DeviceActivity, ManagedSettings frameworks)
• Android UsageStatsManager + AccessibilityService
• Swift/SwiftUI (iOS)
• Kotlin (Android)
• RevenueCat (subscription/lifetime license billing)
• Supabase (lightweight sync/account backend)

Solo + AI difficulty

Android is the easier build — UsageStatsManager plus an Accessibility overlay can track per-app, per-hour usage and block access, gettable to MVP in 2-4 weeks with AI help. iOS is the hard part: Apple's DeviceActivity/ManagedSettings APIs are restrictive about rolling/custom windows and App Store review scrutinizes screen-time-blocking apps, so an iOS MVP will take longer and carries rejection risk.

Entry threshold

A solo developer can ship an MVP using iOS Screen Time APIs (Family Controls / DeviceActivity framework) or Android UsageStatsManager within a few weeks; the main constraint is working within Apple's API limits and app review rather than capital or licensing.

Window

6-12 months

Where to find first users

• r/nocode (where the original request surfaced)
• r/digitalminimalism and similar phone-addiction/dopamine-detox subreddits
• Product Hunt launch
• Indie Hackers / build-in-public posts on X

Competitors

• Opal
• One Sec
• Apple Screen Time
• Android Digital Wellbeing

Counter-signals & risks

• Apple Screen Time and Android Digital Wellbeing are platform-level incumbents that could add per-hour limiting natively, undercutting a third-party micro-app's differentiation.

• Users seeking to curb compulsive scrolling may lack the discipline to engage with a more complex, granular limit-setting UI, reducing retention versus simple daily caps.

• No independent market data or user survey corroborates demand beyond a single anecdotal signal, so willingness to pay for this specific feature is unverified.