Contacts Only – Unknown Call Blocker for Android Phones
- Tools & Troubleshooting, Utilities
- 21 min read
Block Calls from Anyone Not in Your Contacts
Stop spam calls, robocalls, and unknown numbers from ringing your Android phone – without giving up your privacy.
Contacts Only™ is an Android app from Aptora Corporation that does one simple thing: if a caller is not saved in your contacts, your phone does not ring. People you have saved always get through. Everyone else is stopped before your phone makes a sound. There are no ads, no subscriptions, no accounts, and no spam databases to maintain.
This topic will cover what Contacts Only is and how it works, where to get it, how to install and update it, how to set it up step by step, what every control and label on every screen means, tips for getting the most out of it, and answers to the questions we are asked most often. It is written for anyone using an Android phone – no technical knowledge is assumed.
What is Contacts Only?
Contacts Only is a call blocker for Android phones. It is the setting most people wish their phone already had: a single switch that says, “If you are not in my contacts, do not ring my phone.”
Most call-blocking apps try to guess which calls are spam by checking the caller against a database in the cloud, and many charge a monthly fee to do it. Contacts Only does not guess. It applies one rule that you control. If the caller is saved in your phone’s contacts, the call rings normally. If not, the call is stopped according to the settings you choose.
Contacts Only screens telephone calls only. It does not affect text messages, emails, or app notifications. Text messages from unknown numbers still arrive normally.
How Contacts Only Works
Android includes a built-in feature called the call screening role, sometimes shown on your phone as the “Caller ID & spam” app. The app that holds this role is asked about each incoming call before your phone rings, and it answers one question: allow the call, silence it, or block it.
The important part is what Android does before the app is ever consulted. Android checks your contact list itself. Calls from people saved in your contacts ring normally and are never sent to Contacts Only at all. Android only asks Contacts Only about callers who are not in your contacts.
This is why Contacts Only requests no permissions whatsoever. It never reads your contact list, because it does not need to. It also has no internet access, so no information can leave your phone even in principle.
Contacts Only does not run in the background and does not drain your battery. Nothing is running between calls. When a call arrives, Android starts the screening service, receives an answer in a fraction of a second, and shuts it down again. The screen you open is only the settings panel.
Where to Get Contacts Only
Contacts Only is sold on the Google Play Store as a one-time purchase of $2.99 (USD). There is no subscription and there are no in-app purchases.
System Requirements
- An Android phone running Android 10 or newer. The call screening role that Contacts Only depends on was introduced in Android 10, so earlier versions are not supported.
- A phone with calling capability. Contacts Only has nothing to do on a Wi-Fi-only tablet.
- No internet connection is required to use the app after it is installed.
There is no iPhone version of Contacts Only. See the Frequently Asked Questions below for an explanation.
How to Install Contacts Only
- Open the Google Play Store app on your Android phone.
- Search for “Contacts Only” or open the Contacts Only listing directly.
- Tap the price to purchase, then tap Install.
- When the install finishes, tap Open. You can also find Contacts Only later in your app drawer – swipe up from your home screen and look for the blue icon with the white person and green check mark.
How to Update Contacts Only
By default, Google Play updates your apps automatically, so most people never need to do anything. To check for or apply an update manually:
- Open the Google Play Store app.
- Tap your profile picture in the upper right corner.
- Tap Manage apps & device, then Updates available.
- If Contacts Only is listed, tap Update.
Your settings and your blocked call log are preserved across updates. You do not need to set the app up again after it updates.
How to Set Up Contacts Only
Setup takes about thirty seconds and only has to be done once.
Step 1: Turn On Blocking
- Open Contacts Only.
- Turn on the switch labeled Block callers not in Contacts.
Step 2: Approve Contacts Only as Your Call Screening App
The first time you turn the switch on, Android displays a system dialog asking whether you want to make Contacts Only your default caller ID and spam app. This is Android asking, not the app.
- Tap the option that approves Contacts Only in the Android dialog.
- Confirm that the status line under the title now reads “On – only your contacts can ring your phone.” in green.
If you decline, Contacts Only cannot screen calls, and the app will show a card titled One more step with a button to try again. Blocking will stay off until you approve it.
Approving Contacts Only replaces whatever caller ID and spam app you were using, such as Samsung Smart Call. Only one app on the phone can hold this role at a time. You can switch back at any time in Settings.
Step 3: Choose What Happens to Blocked Callers
Under the heading What happens to blocked callers, tap the option you prefer. Go to voicemail is selected by default and is what most people want. Each option is defined below.
That is the entire setup. You can close the app. Blocking continues to work whether or not the app is open, and it keeps working after you restart your phone.
Main Screen Field and Control Definitions
This section defines every control and label on the main Contacts Only screen, in the order they appear.
Title and Status Line
Contacts Only™. The app title at the top of the screen. It is a label only and does nothing when tapped.
Status line. The sentence directly beneath the title that tells you the current state of the app at a glance. It displays one of three messages:
- “On – only your contacts can ring your phone.” (green) Blocking is active and Android has granted the call screening role. Nothing further is required.
- “Almost on – one more step below.” (orange) You turned blocking on, but Android has not granted the call screening role yet. Use the One more step card to finish.
- “Off – all calls ring normally.” (gray) Blocking is turned off. Every call rings, exactly as it would without the app installed.
Block Callers Not in Contacts
Block callers not in Contacts. The master switch, and the only control that is strictly required. When on, callers who are not saved in your contacts are stopped before your phone rings. When off, the app does nothing at all and every call rings normally. All other settings on this screen only matter while this switch is on.
One More Step (Setup Card)
This card appears only when blocking is turned on but Android has not granted the call screening role.
Set as call screening app. A button that re-opens the Android approval dialog. Tap it and approve Contacts Only to finish setup.
Options
Allow repeat callers. A switch, off by default. When on, someone who keeps calling is eventually let through. This is the safety valve for genuine emergencies: if a caller is persistent enough, Contacts Only assumes the call may matter and lets your phone ring. When off, unknown callers are always blocked, no matter how many times they try.
Ring through after. Sets how persistent an unknown caller must be before their call rings. Tap the row and choose 2nd call (the default) or 3rd call. With 2nd call, the first call is blocked and the next call from that same number rings. With 3rd call, the first two calls are blocked and the third rings. This row has no effect unless Allow repeat callers is on, and it is dimmed when that switch is off.
Within. Sets the time window used to count those repeat calls. Tap the row and choose 3 minutes (the default), 5 minutes, or 10 minutes. The caller must call again inside this window for the repeat rule to apply. If they wait longer than the window, the count starts over and they are blocked again. This row is also dimmed unless Allow repeat callers is on.
Allow calls with no caller ID. A switch, off by default. Some callers deliberately hide their number, and sometimes your carrier simply does not provide one. Because there is no number, these callers can never be matched against your contacts, so by default they are blocked like any other unknown caller. Turn this switch on to let them ring instead. Note that this is an all-or-nothing choice: you cannot save a hidden number as a contact, so turning it on lets every hidden number ring, including spam callers who hide their number on purpose. It is also the only way these callers can reach you, because the Allow repeat callers rule cannot help them – with no number, there is nothing to count repeat calls against.
Keep a log of blocked calls. A switch, on by default. When on, Contacts Only records the phone number and time of each blocked call so you can review them later on the Blocked Calls screen. The log is stored only on your phone, is kept for 90 days, and is never sent anywhere. When off, calls are still blocked, but new ones are not recorded.
Schedule
Block on a schedule. A switch, off by default. When off, Contacts Only blocks unknown callers around the clock. When on, blocking applies only during the hours you set below, and unknown callers ring normally outside those hours. This is useful if you only want quiet overnight.
From. The time blocking starts each day. Tap the time to change it. The default is 9:00 PM. This row is dimmed unless Block on a schedule is on.
To. The time blocking stops each day. Tap the time to change it. The default is 7:00 AM. Windows that cross midnight, such as 9:00 PM to 7:00 AM, work correctly. This row is dimmed unless Block on a schedule is on.
What Happens to Blocked Callers
These three options are mutually exclusive. A blue check mark appears next to the one that is active. Tap a row to select it.
Go to voicemail. The default, and what most people want. Your phone never rings and never lights up, and you get no missed call notification. The call is simply not presented to you, so it continues ringing on the caller’s end until your carrier’s voicemail answers it. To the caller, it sounds as though you did not pick up.
Decline immediately. The call is ended at once. The caller hears the call stop quickly. On most carriers, including Verizon, a declined call still lands in your voicemail. Exactly what the caller experiences is determined by your wireless carrier, not by the app.
Silence only. The call is allowed through, but your phone stays silent. The call appears on screen and is recorded as a missed call. Choose this if you would rather see that an unknown caller tried, without being interrupted.
Activity
Blocked Calls. Opens the Blocked Calls screen, described in the next section. The number shown to the right of the label is how many blocked calls are currently stored in your log. It is blank when the log is empty.
Do Not Disturb
This card explains how Contacts Only and your phone’s Do Not Disturb feature work together. It is an explanation, not a setting.
Open Do Not Disturb settings. A link that takes you to your phone’s own Do Not Disturb settings screen, where you can set rules such as allowing only starred contacts to ring. Contacts Only does not change these settings; it only provides the shortcut.
Appearance
Theme. Controls the app’s color scheme. Tap the row and choose System (the default, which follows your phone’s light or dark mode), Light (always light), or Dark (always dark). This affects the appearance of the app only and has no effect on call blocking.
About and Legal
About & Legal. Opens the About screen, described below.
Blocked Calls Screen Field and Control Definitions
This screen is your private record of calls Contacts Only has stopped. It lives only on your phone.
Phone number. The number of the caller who was stopped, formatted for readability. If the caller withheld their number, this reads “Private number.”
Date and time. When the call arrived, shown in your phone’s local time.
Blocked. (red) The call was stopped and your phone never rang.
Rang (repeat call). (green) The caller was persistent enough to satisfy your Allow repeat callers setting, so this call was allowed to ring through.
Rang (no caller ID). (green) The caller hid their number and your Allow calls with no caller ID switch is on, so the call was allowed to ring through.
Silenced. (orange) The call came through silently because Silence only is selected. It appears as a missed call.
Clear. A button in the upper right that deletes the entire log from your phone. You will be asked to confirm. Clearing the log does not change who gets blocked – it only erases the history.
“No blocked calls yet.” Shown when the log is empty. Once Contacts Only stops a caller, they appear here.
“Logging is turned off.” A notice shown when Keep a log of blocked calls is switched off. Calls are still being blocked; they are simply not being recorded.
About Screen Field and Control Definitions
Version. The version of Contacts Only installed on your phone, such as “Version 1.1.0 (2)”. Please include this number if you contact support.
Privacy. A summary of what the app does and does not do with your information.
Privacy Policy. Opens the Contacts Only privacy policy in your web browser.
Terms of Use. Opens the Contacts Only terms of use in your web browser.
Contact Support. Opens your email app with a new message addressed to Aptora support.
Contacts Only and Do Not Disturb
Contacts Only and Do Not Disturb are separate features that work together, and they are easy to confuse. The simplest way to keep them straight:
- Contacts Only decides WHO can reach your phone. Your contacts can; strangers cannot.
- Do Not Disturb decides WHEN your phone makes sound, and for whom among the people who do get through.
- They do not interfere with each other, and turning on one does not affect the other. If you want only your Favorites (starred contacts) to ring, that is a Do Not Disturb setting, not a Contacts Only setting. Turn on Do Not Disturb, allow calls from starred contacts only, and let Contacts Only handle the strangers.
Privacy: What Contacts Only Can and Cannot See
- Contacts Only requests no permissions at all. You can verify this yourself on the Google Play listing, or on your phone under Settings, Apps, Contacts Only, Permissions.
- No internet access. The app cannot send data anywhere, because Android does not grant it the ability to.
- It never reads your contacts. Android checks your contact list itself and only tells the app about callers who are not in it.
- No ads, no tracking, no analytics, and no user accounts.
- The blocked call log is stored in the app’s private storage on your phone, is kept for at most 90 days, and is excluded from cloud backups. Uninstalling the app deletes it.
Tips Related to Contacts Only
- Turn on Allow repeat callers. It costs you nothing and it is the single best protection against missing a genuine emergency from a number you have not saved.
- Save the numbers you care about. The simplest way to guarantee that a doctor’s office, school, or pharmacy always rings is to add them to your contacts.
- If you are nervous about missing calls, start with Silence only. Your phone stays quiet, but you still see that someone tried. Move to Go to voicemail once you trust it.
- Use the schedule if you only want quiet at night. Turn on Block on a schedule and set your hours, and unknown callers will ring normally during the day.
- Do not use Force stop. Force stopping the app in Android Settings prevents Android from starting it for incoming calls, which suspends blocking until you open the app again. Swiping the app away from your recent apps list is perfectly fine and does not stop blocking.
- Turn off your phone’s own private-number blocking. If your Samsung Phone app has “Block unknown/private numbers” switched on, or your carrier runs a service such as Verizon Call Filter, those block calls before Contacts Only sees them. Blocking still happens, but the calls will not appear in your Contacts Only log, and the Allow calls with no caller ID switch will not be able to let anyone through.
- Check your blocked call log occasionally for the first week. It is the easiest way to confirm the app is doing what you expect, and to spot a number you should have saved.
Frequently Asked Questions
Does Contacts Only block text messages?
No. Contacts Only screens telephone calls only. Text messages, picture messages, emails, and app notifications from unknown numbers all arrive normally.
Will I miss important calls from numbers that are not in my contacts?
You can, and we will not pretend otherwise. That is the trade-off of blocking strangers. A new doctor’s office, your child’s school, a pharmacy, or a delivery driver calling from an unfamiliar number will be blocked like any other unknown caller. This is exactly why the Allow repeat callers option exists, and we recommend turning it on. Blocked calls also still appear in your phone’s call history and in the app’s own log, so nothing vanishes without a trace.
Do blocked calls still show up in my phone’s call history?
Yes. Android always records a screened-out call in the system call log as a “Blocked” entry, and no third-party app is permitted to remove it. Contacts Only suppresses the ring and the missed call notification, but the history entry itself is Android’s behavior, not something the app controls.
What does the caller hear when they are blocked?
It depends on the option you choose. With Go to voicemail, the call keeps ringing on their end until your carrier’s voicemail answers, exactly as if your phone were in your pocket. With Decline immediately, the call ends quickly, and on most carriers, they still reach your voicemail. What a blocked caller ultimately experiences is determined by your wireless carrier, not by the app.
Does Contacts Only read my contacts?
No, and it cannot. Contacts Only requests no permissions, including no contacts permission. Android performs the contact check itself and only asks the app about callers who are not saved in your phone. This is also why calls from your contacts always ring: the app is never even consulted about them.
Does Contacts Only need to be open or running?
No. You can close the app completely. Android starts the screening service on its own whenever a call arrives. Nothing runs in the background between calls, so there is no battery drain and no persistent notification.
Does blocking still work after I restart my phone?
Yes, once you unlock the phone the first time after the restart. In the brief window between a restart and your first unlock, Android does not permit any third-party screening app to run, so an unknown caller could ring through during that period. After your first unlock, blocking resumes automatically and stays active. You never need to open the app.
Will Contacts Only replace my Samsung Smart Call or other spam app?
Yes, while it is active. Android allows only one call screening app at a time, so approving Contacts Only replaces the caller ID and spam app you were using. You can switch back at any time under Settings, Apps, Default apps, Caller ID & spam app, or by uninstalling Contacts Only.
Can I allow just one specific number without saving it as a contact?
Not in the app itself. Contacts Only deliberately uses your contact list as the single source of truth for who is allowed. If you want a particular number to ring, save it as a contact. This keeps the rule simple and is what allows the app to work without any permissions.
What happens to calls that show as “No Caller ID” or “Private”?
By default they are blocked, like any other caller who is not in your contacts. A caller who hides their number has no number that could ever match a contact, so Contacts Only stops them. If you need those calls to ring – some medical offices and businesses hide their number on purpose – turn on Allow calls with no caller ID in Options. Be aware that this is all-or-nothing: you cannot save a hidden number as a contact, so every hidden number will ring, including spam callers who hide their number deliberately.
Why do some blocked calls not appear in my Contacts Only log?
Almost always because something else on your phone blocked the call before Contacts Only ever saw it. Contacts Only can only log what Android hands to it. Two common culprits on Samsung phones and Verizon service:
- Samsung Phone app: open the Phone app, tap the three dots, tap Settings, tap Block numbers, and check whether “Block unknown/private numbers” is turned on.
- Verizon Call Filter or a similar carrier service, which blocks at the network level before the call ever reaches your phone.
If either is active, the call is stopped upstream and never reaches Contacts Only. It looks identical to you – your phone does not ring – but there is nothing for the app to record. Turning those off lets Contacts Only handle the call and log it.
Can Contacts Only let just one hidden number through?
No. Callers who hide their number cannot be identified, so there is no way to tell one apart from another. The Allow calls with no caller ID switch is all-or-nothing by necessity. If a caller who matters to you hides their number, ask them to call from a number you can save as a contact.
Does Contacts Only work with Do Not Disturb?
Yes. The two are completely independent and work well together. Contacts Only decides who can reach your phone; Do Not Disturb decides when your phone makes sound. Turning on one does not change the other.
How do I let only my Favorites ring?
That is a Do Not Disturb setting rather than a Contacts Only setting. Turn on Do Not Disturb and set it to allow calls from starred contacts only. Contacts Only continues to stop everyone who is not in your contacts at all. There is a shortcut to your Do Not Disturb settings on the main screen.
How much does Contacts Only cost? Is there a subscription?
Contacts Only is $2.99 (USD) one time, on the Google Play Store. There is no subscription, there are no in-app purchases, and there are no ads. You pay once and own it.
What version of Android do I need?
Android 10 or newer. Contacts Only relies on the Android call screening role, which Google introduced in Android 10. It cannot work on earlier versions.
Is there an iPhone or iOS version of Contacts Only?
No, and there cannot be one. Apple does not provide any way for a third-party app to screen incoming calls against your contacts as they arrive. Apple builds this capability into iOS instead: open Settings, tap Phone, and turn on Silence Unknown Callers. Android has no equivalent built-in setting, which is precisely why Contacts Only exists.
Does Contacts Only need an internet connection?
No. The app has no internet access at all, by design. It works entirely on your phone, including in airplane mode over Wi-Fi calling or anywhere with no data connection.
How do I turn Contacts Only off?
Open the app and turn off the Block callers not in Contacts switch. Every call will ring normally again. Your settings and log are kept in case you turn it back on. To remove it entirely, uninstall the app like any other app; this also deletes your blocked call log.
Where is my blocked call log stored, and can anyone else see it?
It is stored in the app’s private storage on your phone, which other apps cannot read. It is never transmitted anywhere, because the app has no internet access, and it is excluded from your phone’s cloud backup. Entries are deleted automatically after 90 days, and you can erase the whole log at any time with the Clear button on the Blocked Calls screen.
