There's a reasonable question behind the search for monitoring apps: which tool to use to track a child's cell phone, locate a lost device, or manage a team's devices? This comparison covers the options that are legal, actually work, and are still available in official app stores — and tells you what each one delivers, what it charges for, and where it falls short.
The rule that defines what goes into this list.
Only monitoring tools are allowed. declaredThe app is visible on the device, and the person knows they are being tracked. This is a requirement of Google Play's policy, and it's also what separates legal use from crime.
Monitoring an adult without their consent constitutes unauthorized access to a computer system., Article 154-A of the Penal Code, with imprisonment from 1 to 4 years and a fine. Therefore, covert surveillance tools do not appear here — not because they are bad, but because their advertised uses are illegal.
Google Family Link — the default choice on Android
Price: free. For whom: Parents of minors.
It does the essentials and does them well: daily screen time limit, separate limits per app, bedtime with automatic blocking, mandatory approval to install anything, content filters on Play, Chrome, and YouTube by age rating, and device location.
Where it fails: It doesn't show the content of conversations—on purpose. Older teenagers find ways around it, like using a friend's device. And supervision ends automatically when the child turns 18.
Google Family Link
AndroidApple Screen Time — native to iPhone
Price: Free, already included in the system. For whom: Families in the Apple ecosystem.
Configured by Family Sharing, it offers Screen Time, limits by app category, content and privacy restrictions, purchase controls, and blocking of adult content on the web. Protected by a separate passcode from the unlock key.
Where it fails: It only works between Apple devices. If you have a mixed family, you end up managing two different systems.
Qustodio — when the report needs to be more detailed
Price: Subscription, with a limited free version. For whom: Families seeking more granular and multi-platform support.
It covers Android, iOS, Windows, and macOS in a single dashboard, with usage reports by app and website, filters by category, and time limits. Useful when children use computers as much as cell phones.
Where it fails: It's a paid annual subscription, and the free version offers very little. For those who only need to control one Android phone, Family Link is a free option.
Bark — focus on warning signs, not on full reading.
Price: signature. For whom: Families concerned about specific issues, such as bullying or self-harm.
The proposal differs from others: instead of delivering all the content to parents, the service analyzes and alerts them only when it identifies signs of risk. It's a design that better preserves the teenager's privacy and tends to generate less friction.
Where it fails: Feature coverage varies considerably depending on the platform and application, and the service is primarily geared towards the United States market.
Find My Device and Find My iPhone — for lost devices
Price: Free, native.
They solve the most common problem of all, which isn't surveillance but loss. They locate the device on a map, sound an alarm even on silent mode, lock the device with a message on the screen, and remotely erase data. It's worth checking today if they're activated—once the device is lost, it can't be configured again.
MDM Solutions — The Corporate Path
Price: per device, contracted by the company. For whom: organizations that supply devices.
They implement security policies, distribute applications, separate work and personal profiles, and allow remote erasure of corporate data in case of loss or termination. This is legal as long as the policy is communicated in writing and restricted to professional use—the employee's personal device is off-limits, even if they use it for work.
Quick comparison
- Child on Android, free of charge: Family Link.
- Son on iPhone, free of charge: Usage Time.
- Family with cell phone and computer, multiple systems: Qustodio.
- Concern about emotional risk, less reading of content: Bark.
- Lost or stolen device: Find My Device or Find My iPhone.
- Corporate fleet: MDM contracted on behalf of the company.
- Combined location between adults: Native sharing from Google Maps or Search.
Which none of them do
None of them display the content of WhatsApp, Instagram, or Telegram conversations. Messages are end-to-end encrypted, and official store policies do not allow this type of access. Any product that promises this is not available in stores, requires manual installation with the device in hand, and, if applied to an adult without consent, is a crime.
There is also no such thing as monitoring "just with the number." That's the promise that identifies fraud more accurately.
Frequently Asked Questions
Which is the best free one?
Family Link on Android and Screen Time on iPhone. For most families, these solutions are free.
Is it worth paying for Qustodio or Bark?
It's worthwhile when there's a specific need: multiple operating systems in the house, or monitoring for warning signs after a situation has already been identified. For simple control of a cell phone, it's not worth it.
Can I use these tools on my partner's cell phone?
Only with his informed and revocable consent. Without it, it's a crime.
Do they work after the child turns 18?
No. Parental supervision is terminated, and from that point on, the only legal recourse is with explicit consent.
Do they consume a lot of battery?
Official programs have little impact because they are integrated into the system. High power consumption and overheating usually indicate an unofficial program installed.
In summary
For child supervision, the native tools are free and sufficient; paid ones make sense in specific scenarios. For lost devices, the system's own solution works. For businesses, MDM with a signed policy is sufficient. And none of them read conversations—anything that promises to do so is either illegal, out of the question, or a scam.
How to use it in practice
- Use the official tool. Google Family Link on Android and Screen Time on iPhone: free, visible on the device, and without requiring you to disable any protection.
- Combine before configuring. With a teenage child, an agreement on what will be monitored is worth more than any restriction—and survives discovery better.
- Review the agreement every few months. Limits that don't match age become a source of conflict and challenges.
- Enable installation approval. It prevents new apps from appearing without your knowledge, which is half the problem.
What goes wrong most often?
- Relying on evidence obtained through unauthorized access in a legal proceeding—it is discarded and exposes whoever produced it.
- Expecting to read WhatsApp conversations: end-to-end encryption prevents this, for any tool.
- Disabling Play Protect to install files from outside sources is the most common vector for banking trojans.
- Don't believe promises of monitoring based solely on a phone number; it doesn't exist.
The alternative that is already included in the system
To find a lost device, Find My Device and Find My iPhone are free and come standard: they sound an alarm even when the device is on silent, show it on a map, and remotely lock and erase it. It's worth checking today if they are activated — once lost, you can't configure them anymore.
