Support Documentation
Overview
Block It Out automatically synchronizes calendar events across multiple accounts while protecting your privacy. Create “shadow events” that block out your time without revealing sensitive details. Available for iOS via AppStore.
How It Works
Core Functionality
When an event appears in your source calendar, the app creates a “shadow event” in your destination calendar(s). The shadow event blocks out the time but contains only generic information to protect your privacy.
This is all done in the app on your phone. There is no accompanying service to be attacked or fail.
Common Use Cases
Work-Life Balance
- Sync personal appointments to work calendar as “busy” blocks
- Maintain privacy while preventing scheduling conflicts
- Automatically block travel time and personal commitments
Work-Work Balance
- Sync your availability across competing clients
- Maintain clear availability across your multiple ventures, or your day job and your side hustle
- Give your EA access to availability across external commitments without divulging sensitive information
Multi-Calendar Management
- Keep client calendars updated without manual effort
- Synchronize between iCloud, Google, Exchange, and Outlook
- Manage availability across multiple business accounts
Team Coordination
- Share availability without exposing meeting details
- Coordinate schedules across different calendar systems
- Maintain professional boundaries with custom shadow titles
Subscription Tiers
- Free Tier
- 1 sync rule maximum
- 1 destination calendar specified in the rule
- Basic shadow event creation with “Block” title
- Background sync for automatic updates
- Essential Tier
- Up to 2 sync rules
- 1 destination calendar per rule
- Privacy filtering to selectively sync events marked private
- Custom shadow titles instead of the generic “Block”
- Advanced Tier
- Unlimited sync rules
- Multiple destination calendars per rule
- Advanced filtering with complex conditions
- Hierarchical logic (nested AND/OR groups) for sophisticated rules
- Custom shadow templates for shadow events
- Custom reminders & notifications for shadow events
- Transaction rollback system for selective undo operations
Getting Started
Setting Up Your First Rule
- Grant Calendar Access: Allow the app to read and write to your
calendars
- Choose Source Calendar: Select the calendar with events you want to
sync
- Choose Destination Calendar(s): Select where shadow events should
appear
- Configure Filtering (Essential/Advanced): Set conditions for which
events to sync
- Customize Shadow Events (Essential/Advanced): Set custom titles and
templates
- Save rule: Background Sync is automatic for all users
Advanced Features
Event Filtering
Create sophisticated rules to sync only specific events:
- Filter by event title (contains, equals, starts with, ends with)
- Filter by event duration (less than, exactly, more than X minutes)
- Combine conditions with nestable AND/OR logic
Time Padding
Add buffer time around your shadow events:
- Configure minutes before events (e.g., travel time, prep time)
- Configure minutes after events (e.g., wrap-up, debrief)
- Shadow events automatically extend to include padding
Custom Notifications
Control alerts for shadow events independently:
- Enable/disable notifications per rule
- Choose from preset times (5, 15, 30 min, 1 hour, etc.)
- Set custom alert times in minutes
Template Variables
Create dynamic shadow event titles using placeholders:
{shadowTitle} - Your configured shadow title{originalTitle} - The source event’s title{location} - The source event’s location{duration} - The event duration (e.g., “60 min”)
Dry Run Preview
Preview exactly what will happen before syncing:
- See summary of events to create, update, and delete
- Review per-destination breakdown with expandable event lists
- Compare original titles with shadow titles
- Confirm and run sync directly from preview, or cancel
Undo Last Sync
Quickly revert the most recent sync operation:
- One-tap undo for each rule’s last sync
- Confirmation dialog shows number of events to remove
- Deletes shadow events created by that sync
- Transaction history tracks all operations
OE Obfuscation
Enhanced privacy with randomized shadow titles:
- Select categories of activities (Health, Fitness, Errands, etc.)
- System generates believable random titles from your selected categories
- Usage tracking prevents the same title from appearing too frequently
Optional Calendar Analysis: When enabled, the app examines your selected calendars to learn your actual activity patterns. It counts how often events with keywords like “gym”, “trainer”, “doctor”, etc. appear in your real calendar, then sets frequency limits for generated titles to match. For example, if you typically have 4 gym-related events per month, it won’t generate 20 “Gym” shadow titles—that would look suspicious to anyone viewing your calendar. This is simple keyword counting, not AI or machine learning.
Background Synchronization
- Automatic syncing (when iOS allows)
- Real-time notifications when changes occur
- Works even when the app is closed
Troubleshooting
Background Sync Not Working
- Enable Background App Refresh in iOS Settings → Apps → Block It Out → Background App Refresh
Events Not Syncing
- Verify calendar permissions in iOS Settings → Apps → Block It Out → Calendar → Full Access
- Ensure source and destination calendars are accessible
- Check that your rule conditions aren’t too restrictive (consider using Dry Run to test changes)
- Try running Sync from the app, to validate the problem is not with the background refresh functionality
Shadow Events Missing Details
This is intentional for privacy. Upgrade to Essential or Advanced to
customize shadow event content.
Privacy & Security
- Your data stays on your device - no cloud storage of calendar data
- Source events are never modified - only shadow events are created
- Granular privacy controls - choose exactly what information to share
- Safe operations - transaction system prevents data loss
Support
Getting Help
- Email: support (at) block-it-out (dot) com
- In-App Logs: Use the logs viewer for detailed sync information (enable debug)
- Crashes: I should see crashes if you’re sending them to Apple, and I’ll do my best to fix them ASAP.
Recently Added (Advanced Tier)
- Dry Run Preview: See exactly what sync will do before executing—review creates, updates, and deletes with full event details
- Undo Last Sync: One-tap revert of the most recent sync operation for any rule
- Real-Time Sync Progress: Live progress bar and status updates during sync operations
- Time Padding: Add buffer time before/after shadow events (e.g., 15 min before meetings for travel)
- Custom Notifications: Configure alerts for shadow events separate from source events
- Template Variables: Use placeholders like
{originalTitle}, {shadowTitle}, {location}, {duration} in shadow event titles
Feature Requests
I’m not just the author, I’m also a client. Block It Out was born from my own needs and I’m always interested in its improvement. If you have a feature you’d like to see, please send me a note with suggestions for new features or improvements. Things I’m working on:
- An in-app calendar view that ignores the shadows
Subscription Management
- Manage subscriptions through your Apple ID account settings
- Use “Restore Purchases” in the app if you’ve reinstalled
- Subscriptions auto-renew unless cancelled in accordance with AppStore rules
Frequently Asked Questions
Q: Can I sync events between Google Calendar and iCloud? How about Exchange?
A: Yes! As long as the calendars are accessible through the iPhone’s native Calendar app, Block It Out can sync between them.
Q: Will this work with recurring meetings?
A: Absolutely; recurring events maintain their recurrence patterns in the shadow calendar.
Q: If I move an event, will Block It Out notice?
A: Yes, the app keeps an identifier in the shadow which helps it know what’s been done without having to keep a massive database of all your events.
Q: Can I customize what information appears in shadow events?
A: With Essential or Advanced subscriptions, you can customize shadow titles.
Q: How often does background sync run?
A: With Essential or Advanced subscriptions, the app asks to sync every 5 minutes, but iOS controls the actual frequency based on your usage patterns, battery life, and other events.
Q: What happens if I delete a rule?
A: The app will offer to clean up all shadow events created by that rule, keeping your calendars organized.
Q: Will you build this for Android?
A: I have no plans to build this for Android, but someone should! These techniques are not magic. If you would like to develop this for Android and want to talk about it, I’m happy to help.
Q: Is my calendar data sent to any servers?
A: No. All synchronization happens on your device. No calendar data is transmitted by the app EVER, for any reason.
Q: Do you have the password to my account?
A: No. All access to calendars on the device happens without any need for passwords or other form of authentication.
Q: How is this different from other solution?
A: When I first built this app, I didn’t publish it. I wasn’t sure people needed it. But over the years, I watched other solutions appear. They all had one thing in common: cloud services storing your credentials to sync your calendars.
OneCal. FreeBusyIO. Reclaim AI. CalendarBridge. SyncGene. SyncThemCalendars. Zapier. Sync2 Cloud. Different names, same idea. Your private data lives on someone else’s server.
Many of them offer extras—scheduling tools, automation, integrations. But the moment a service collects credentials for thousands of calendars and inboxes, it becomes a target.
Hackers don’t sleep, especially the AI Agentic Swarming hackers of today. Defending against them takes more than luck. As Mr. Miyagi said, “Best block? No be there.”
That’s why I made Block It Out. If you want the sync without the risk-no servers, no middlemen-this app is for you.
Q: I’m an admin, and the people I support have conflicting personal appointments. How can I use this app to help?
A: If this app is installed on their phones, they can set up a rule to watch their personal calendar and block out time in their work calendar. That way, you can schedule around that time. The free tier allows for one rule, so they can try it out at no cost. If they’d like to selectively block out the time, based on a key word or other attribute, it requires a subscription.
Privacy Policy
Block It Out is committed to protecting your privacy. All data processing occurs entirely on your device - your calendar information is never collected, stored, or transmitted.
View Full Privacy Policy →
© 2025 Isaiah Weiner. All rights reserved.