Hacker: Secret Codes & Ciphers

Review by eFreeware

Hacker: Secret Codes & Ciphers is a free reference app from Vidmark Inc. that collects Android secret codes, hidden menus and USSD strings in one place. It sits in the Libraries & Demo category, and with more than 5 million installs it has clearly found an audience beyond the developer's own circle.

The appeal is straightforward. Instead of hunting through forums for a working dialer string, you keep a searchable list on your phone and pull up the code when you need it. The developer describes it as a guide to hidden features and advanced settings, and that is the job it sets out to do.

It is not a tool that changes your phone by itself. You still dial the codes, read the results and decide what to do next. That distinction matters, because a good reference is only as useful as the person holding it.

An offline catalog of dialer codes and hidden menus

The feature the developer leads with is an offline list of secret codes. That means the catalog is available without a connection, which is the sensible choice for something you might want to consult in a basement, on a plane or anywhere else without a reliable signal.

The codes themselves cover the usual ground: hidden menus, hardware tests and settings that are not exposed through the normal interface. In practice these strings are dialed into the phone app like a regular number. The app's role is to tell you which string to try.

USSD codes are part of the same collection. These are the short strings used for things like checking a balance or managing a service. Keeping both kinds in a single reference saves you from remembering which is which.

The developer also promises regular updates with new codes. That matters more than it might sound. Codes come and go as manufacturers change their firmware, so a static list goes stale, and a maintained one stays useful for longer.

What else the app puts in one place

Beyond the core catalog, the developer groups the content under a few broad purposes: fixing issues, running tests, saving time and customizing the phone. These are less separate features than ways of describing the same body of codes, but the framing is helpful when you are trying to work out which string to reach for.

The app is pitched at a wide range of users. Tech enthusiasts, professionals and DIY tinkerers all get a mention, and the content rating is Everyone, so nothing here is gated behind an age check. The app presents its codes as trusted, which is the sort of claim I would treat as marketing rather than a guarantee.

The most recent update, from October 6, 2026, mentions performance improvements for faster code discovery and smoother navigation, along with bug fixes. If you have used an earlier version and found it slow to browse, that is the change to look for.

What the app is not is a diagnostic suite in its own right. It does not run the tests for you; it points you at the menus where the tests live. The distinction is worth holding onto, because it shapes what you should expect from the first few minutes.

What it asks of you: a phone, a dialer and some patience

The requirements are modest. You need the willingness to dial codes into your phone. The catalog is described as offline, so consulting the list does not depend on a connection.

On cost, the app is free to download and supported by ads, and it offers in-app purchases. Treat the free download as the starting point and see what the app presents once it is on your device.

The other cost is time and care. Some codes open menus that are meant for service technicians, and changing a setting you do not understand can leave you worse off than you started. The app gives you the string; the judgment about whether to send it is yours.

There is also the matter of compatibility. Compatibility can vary from one handset to another. Expect some trial and error as you work through the list.

Getting value out of a code reference

The sensible way to use an app like this is to start with a question rather than a code. If you want to check whether a sensor is working, or find out why a connection is misbehaving, look for the category that matches the problem and read the surrounding description before dialing anything.

Keep the app installed rather than treating it as a one-off download. The value of a reference grows when it is there at the moment you need it, and the developer's commitment to adding new codes means the list should shift over time. Checking back after an update is a reasonable habit.

It also helps to note which codes actually worked on your handset. The useful ones tend to be a small subset of any general list. A little personal record-keeping turns a broad catalog into something tailored to your phone.

If you are the sort of person who enjoys poking at settings and understanding what a device is doing under the surface, this is a natural fit. If you would rather not risk an unfamiliar menu, the catalog will still be interesting to read, but the practical payoff is smaller.

A 3.9 average and what it suggests

The app holds a 3.9 rating from 28,891 ratings, with 360 written reviews. That is a solid but not stellar score, and it is the kind of number that usually reflects a mix of people who found the code they needed and people who did not. A reference app lives or dies on whether the specific string you want is in the list.

The install count of over 5 million tells a similar story. This is a widely used utility rather than a niche curiosity, which means the developer has a large enough audience to justify keeping the catalog current. The October 2026 update is consistent with that.

I would not read too much into the rating either way. Codes are inherently hit-or-miss across manufacturers, and a low score from one user's handset may be a perfect score on another's. The average is a rough signal, not a verdict on the app's usefulness to you.

A handy reference for people who like to tinker

Hacker: Secret Codes & Ciphers does one job and does it without much fuss: it puts a large collection of Android codes and USSD strings in your pocket, offline and in one place. The developer keeps adding to it, and the recent performance work suggests the browsing experience has been tidied up.

It suits tinkerers, technicians and anyone curious about the menus their phone keeps out of sight. It is free, ad-supported and offers in-app purchases, so trying it costs nothing but the time to look through the list. If you want a single place to consult when a hidden setting or a diagnostic screen would help, this is a reasonable addition to your phone.

Go in expecting a reference rather than a magic wand. For the right user, that trade-off is easy to accept.

What's new in version 2.3.0

🚀 Update: - Enhanced performance for faster code discovery and smoother navigation ⚡ - Bug fixes for reliable, seamless use across devices 🛠️