Law of Common Region

Elements tend to be perceived into groups if they are sharing an area with a clearly defined boundary.

The scenario: a mobile app's notification settings — twelve toggles. Both versions contain the exact same twelve settings with the exact same on/off states; only the visual boundaries change. Watch how four bordered cards turn an unscannable wall into four quick questions.

What's wrong here? Twelve toggles in one flat list, in no particular order. To find “turn off marketing emails but keep security alerts” a user must read every single row, because nothing tells the eye where email ends and push begins. Most people give up and either mute everything or nothing.
taskhub.app/settings/notifications

Notifications

Manage how TaskHub notifies you.

Email digest
Push for mentions
SMS alerts
Marketing emails
Weekly report
Sound
Badge count
Security alerts
Product updates
Reminders
Team activity
Quiet hours

🔍 What changed

  • Nothing was added or removed — the same 12 settings with the same states appear in both versions.
  • Four bordered cards create four common regions: Email, Push, SMS & Sound, Security.
  • Short uppercase card headers let users skip whole groups they don't care about.
  • Related settings that were scattered through the flat list (e.g. all email options) now sit inside one boundary.

💼 Explaining it to stakeholders

“A boundary is the cheapest information architecture there is. Drawing four boxes around the same twelve settings means users scan four labels instead of reading twelve rows — settings screens stop generating ‘how do I turn this off?’ support tickets, and people who can control their notifications precisely are far less likely to disable them entirely.”