I keep a lot of sensitive documents on my phone because I need them at short notice. However, having them scattered across my storage and accessible in plain sight started to bother me.

My first instinct was to buy a vault app, one of those premium Play Store products with the intimidating icon and the long list of security claims. Adding another line to my debit card statement was not a thought I particularly enjoyed.

As a delay tactic, I sorted through the documents I already had so I could move all of them over at once. That's when I found the thing that made the purchase unnecessary: the Files app installed on my phone.

I have always used Files to find and clear wasted storage, but turning on a few features I had been ignoring changed what it was good for.

Files' great (not so hidden) features

Greater than the sum of their parts

It started with the Safe Folder option near the bottom of the main menu. I had seen it before and even set it up once, then never opened it again.

Files encrypts what goes in there, locks it behind a PIN or pattern, and seals it the moment you switch away from the app, so nothing shows up while Files is in the background.

My problem was that I had no idea what PIN I set when I got the phone. Settings let me reset the folder at the cost of everything inside it, which cost me nothing, since it was empty (or at least I hoped it was).

While I was there, I found the toggle for smart search, which was already on and which I had never looked into. The learn more link is what got my attention.

It lets Files index the contents of documents and images so you can search using their contents rather than just their names. I have wasted more time than I want to admit opening badly named business documents only to search for a couple of lines.

The last component was the scanner built into Files, which I had never bothered with. That changed after I realized how dated and blurry some of my existing scans were.

How it all comes together

Easy as easy comes

None of these features are new, and none are impressive on their own. It was my specific need that revealed how powerful the synergy between them can be.

I used smart search to pull up every important document on the phone, renamed them properly, and moved them into the Safe Folder.

Anything too blurry to trust was rescanned with the built-in scanner. I renamed each generated PDF and moved it across, which is when I stopped missing Microsoft Lens, an app Microsoft has since retired.

In under an hour, I had a clean set of labeled documents, encrypted and locked behind a PIN.

When files are in there, they vanish as far as the rest of the phone is concerned, and that's the point. If a vault shows up in search results, it is not a vault.

Now I spend a few minutes at the end of each week moving new work documents in. With the scanner and smart search, it's pretty much effortless.

How it's different from the paid options

The good, the bad, and the unnecessary

I've looked into vault apps before, so I arrived with expectations and a list of complaints I hoped to leave behind. The difference was the implications of local-only storage on data recovery.

There is no recovery. If you forget your PIN, the only option is resetting the folder, which wipes everything in it.

Google also warns that Safe Folder files can occasionally corrupt, especially when triggered by other apps clearing storage. This is rare, though, as long as you don't trust third-party cache cleaners or move the encrypted files.

As a vault, the files are tied to the phone. They won't open if you move them to another device, since they're encrypted using the device's unique storage state.

Since most of the files in my vault have a physical copy, I can deal with an afternoon of rescanning rather than paying premium bucks for a dedicated vault app.

My documents are in good (and free) hands

It has been a few months, and the setup continues to work well without a new app or a subscription.

I'd nearly paid for a worse version of something already installed, which is a habit I'm actively trying to cut, especially when several Google apps that ship with the phone go unopened.

Before, I used Files almost exclusively to find saved downloads, and I ran a different app as the main file manager. It has since replaced two apps, and my documents are digitized, labeled, and locked away.