Essential Phone Privacy Settings Everyone Should Change

iPhone Privacy Settings

On iPhone (iOS 16 and later), the most impactful privacy settings are in Settings → Privacy & Security. Start with Location Services: review which apps have "Always" location access and change all non-navigation apps to "While Using" or "Never." Social media, games, and shopping apps have no legitimate need for your location at all, and their location data is frequently sold to data brokers who build detailed profiles including your home address, workplace, and daily routine. Tap each app under Location Services and review the setting individually.

Next: Settings → Privacy & Security → Tracking. Enable "Ask Apps Not to Track" — this prevents apps from cross-referencing your iPhone's IDFA identifier with other apps and websites to build a unified advertising profile. Settings → Privacy & Security → App Privacy Report (enable it) shows which apps have accessed your camera, microphone, contacts, and location in the past 7 days — review this weekly. Any app accessing your microphone or contacts when you haven't used it is a concern worth investigating. Settings → Phone → Silence Unknown Callers blocks calls from numbers not in your contacts, not in your recent calls, and not in Siri Suggestions. Settings → Messages → Filter Unknown Senders routes unknown sender texts to a separate folder and disables link previews — critical smishing protection.

Additional settings: Settings → General → VPN & Device Management — review any installed profiles. Settings → Privacy & Security → Analytics & Improvements → toggle off "Share iPhone Analytics" and "Share with App Developers." Settings → Privacy & Security → Apple Advertising → toggle off "Personalized Ads." Settings → Privacy & Security → Safety Check (iOS 16+) lets you review which apps and people have access to your data and location — useful for annual privacy audits. For maximum call privacy: Settings → Phone → Show My Caller ID → toggle off if you don't want your number displayed when you call others (though this also means some people may not answer your calls).

Android Privacy Settings

Android privacy settings vary by manufacturer (Samsung, Google Pixel, OnePlus), but all Android 12+ devices include Google's baseline Privacy Dashboard at Settings → Privacy → Privacy Dashboard. This dashboard shows a 24-hour timeline of which apps accessed your location, camera, microphone, contacts, and calendar. Settings → Privacy → Permission Manager shows every permission category and which apps have each permission. Remove microphone access from any app that doesn't need it for its core function; remove "Precise" location access from social and shopping apps (change to "Approximate" if location access is genuinely needed at all).

Settings → Privacy → Ads → Delete Advertising ID (Android 12+) removes your device's advertising identifier entirely, preventing ad networks from building cross-app behavioral profiles. This is more aggressive than iOS's "Ask Apps Not to Track" and more effective at fragmenting your ad profile. Settings → Phone → Caller ID & Spam → "Filter spam calls" enables Google's carrier-independent spam detection — works even if your carrier doesn't offer spam filtering. Settings → Messages → Spam protection enables Google's smishing detection, comparing incoming text patterns against known phishing signatures. For Samsung Galaxy devices specifically: Settings → Security and Privacy → Permission Manager, and Settings → Privacy → Permission Monitoring sends notifications when apps access sensitive permissions unexpectedly.

Google-specific account privacy (relevant for all Android users with a Google account): myaccount.google.com → Data & Privacy → Web & App Activity — pause activity tracking if you don't want your phone usage to build your Google profile. myaccount.google.com → Data & Privacy → Location History — pause and delete if you don't want Google storing your GPS history. These Google account settings are separate from phone settings and affect all Google-connected devices including Chromebooks and browsers. For highest-privacy Android configuration, GrapheneOS (grapheneos.org) is an open-source Android fork that removes Google services and provides significantly enhanced privacy at the cost of compatibility with Google-dependent apps.

App Permission Auditing

Permission auditing is the process of reviewing which apps have access to which data categories and revoking access that isn't necessary for the app's core function. Conduct a full audit when you first set up a new phone, then repeat quarterly. The permissions most frequently abused by data-hungry apps: Contacts (allows uploading your entire address book to their servers), Microphone (allows ambient audio recording on some Android versions), Location (enables tracking of your home, work, and travel patterns), and Storage (allows reading all files on your phone, including photos and documents).

Specific apps to scrutinize: free games and flashlight apps have historically been the most aggressive at requesting unnecessary permissions. Any app requesting Contacts that isn't a messaging or calling app should be denied. Any app requesting Microphone that isn't a communication or voice recording app should be denied. Social media apps (Facebook, TikTok, Snapchat, Instagram) should have location set to "While Using" at most, and microphone access is only needed when you're actively recording. Check whether Facebook has "Background App Refresh" enabled on iPhone (Settings → General → Background App Refresh) — disable it for social apps that don't need real-time updates when you're not using them.

For a complete audit, use the built-in platform tools: iOS Privacy Report (Settings → Privacy & Security → App Privacy Report → turn on) and Android Privacy Dashboard (Settings → Privacy → Privacy Dashboard). These show which apps have accessed permissions in the last week. If an app you rarely use shows consistent background location or microphone access, either revoke those permissions or uninstall the app. An app with no legitimate need for sensitive permissions that accesses them repeatedly is exhibiting data harvesting behavior — and that data is likely sold to brokers who sell to telemarketers and potentially to scam operations that use personalized information to make their calls more convincing.

Location and Tracking Controls

Location data is among the most commercially valuable personal data categories because it reveals your home address (where you sleep most nights), your workplace, your medical appointments, your religious affiliation, and your political activities. The data broker industry built a multi-billion dollar business on monetizing precise location data collected by mobile apps — Senate Commerce Committee investigations (2023-2024) documented the scale of this ecosystem in detail. Limiting app location access is one of the highest-impact privacy actions available on your phone.

Beyond app permissions, your carrier always knows your approximate location through cell tower connections — inherent to cellular network function and cannot be disabled without disabling service. What you can control: iPhones Settings → Privacy & Security → Location Services → System Services — disable "Significant Locations" (Apple's location history log) and "iPhone Analytics." Google Maps users should review Timeline settings at maps.google.com/maps/timeline — delete all stored location history and disable Timeline collection. Google's "Delete activity by" feature at myactivity.google.com allows setting automatic location history deletion at 3-month intervals.

Advertising-based location tracking uses sensor fusion — apps access the accelerometer, WiFi access point lists, Bluetooth beacons, and barometric pressure sensors to infer location even without GPS permission. While you cannot entirely prevent sensor-based location inference, you can reduce its commercial use by deleting your advertising ID (Android) or opting out of personalized ads (iOS). For high-sensitivity situations — domestic violence safety planning, for example — the National Domestic Violence Hotline (thehotline.org) publishes specific guidance on phone privacy for safety-critical situations. For journalists and activists in high-risk environments, the Committee to Protect Journalists (cpj.org) and EFF's Surveillance Self-Defense (ssd.eff.org) provide threat-model-specific guidance beyond what these general settings address.

Settings That Reduce Spam Calls

Beyond carrier-level spam filtering (which should always be enabled), several on-device settings directly reduce the volume of unwanted calls. iPhone: Settings → Phone → Silence Unknown Callers sends calls from numbers not in your contacts, recent calls, or Siri Suggestions directly to voicemail without ringing. This is the most aggressive built-in option. For less aggressive filtering: settings through third-party call blocking apps (Hiya, RoboKiller, Nomorobo) appear in Settings → Phone → Incoming Calls and integrate directly with the Phone app. Android: Phone app → three-dot menu → Settings → Blocked numbers → enable "Unknown" to block calls marked as unknown or private. Google Phone's "Screen calls" feature (available on Google Pixel) uses Google Assistant to ask unknown callers to identify themselves before the call reaches you.

Third-party call blocking apps provide significantly more robust protection than built-in carrier tools. Hiya (hiya.com) — available for both iOS and Android — uses a database of 450 million reported spam numbers and provides real-time call labeling integrated with the native Phone app. RoboKiller ($4.99/month) uses audio fingerprinting to detect robocall patterns and provides "Answer Bots" that waste scammers' time by keeping them engaged with an AI voice. Nomorobo (nomorobo.com, $1.99/month for mobile) is particularly effective against VoIP robocalls and was the winner of the FTC's 2013 Robocall Challenge. All three are superior to relying solely on carrier tools because their databases are continuously updated with current scam number patterns.

Register your number at donotcall.gov (or call 1-888-382-1222) if you haven't already — it won't stop scammers but does reduce legitimate telemarketing calls, reducing total call volume and making scam calls easier to identify by ratio. For landline users, the CPR Call Blocker V10000 and V5000 models maintain a database of 10,000 blocked numbers with a single-button block for new numbers — these hardware devices are effective for households where the resident is less comfortable with smartphone apps but still needs protection from high-volume robocalls. Nomorobo also offers a landline version for $1.99/month that works with VoIP-based home phones through simultaneous ring interception.