Lumen

The smart features of Google Photos and the iPhone Photos app, for Android.
Nothing leaves your phone.

▶ Watch the launch video, 37 seconds

Lumen is a photo gallery for Android. It does the same tasks as Google Photos and the Photos app on iPhone. It finds a photo from a description, reads the text in your photos, puts the photos of each person together, and cuts a person out of a photo. Lumen does all of this work on your phone. Your photos, your faces, and your index never leave it.

Google Photos does this work on the servers of Google, and you must have a Google account. The Photos app on iPhone does the work on the phone, but it is only for Apple devices. Lumen gives you the same features on Android, without Google and without the cloud.

• No account. You do not sign in to Google or to Lumen.
• No Google Play services. Lumen does not use them, so it works on phones without Google apps.
• No cloud. Lumen does not send your photos or their data to a server.
• No advertisements, no analytics, and no tracking.
• Works offline. After you download the models one time, the smart features work without the internet.
• Open source. Anyone can read and do a check of the code.
• No cost.

✅ Lumen has it · ◐ Lumen has part of it · 🚧 Lumen is working on it · ❌ Lumen does not have it

• Why Lumen
• Lumen and Google Photos
• Features
• Privacy
• Requirements
• Install Lumen
• Smart features
• Faster on Snapdragon
• Permissions
• Build Lumen from the source code
• Report a bug
• License

• See all of your photos and videos in one grid. The newest photo is at the bottom.
• New photos and screenshots appear at once.
• Pinch the grid to show more or fewer columns.
• Show the photos by year or by month.
• Show only photos, videos, favorites, or screenshots. Sort by date, name, or size.
• See each folder on your phone as an album. Sort, pin, rename, and set the cover of an album. Tap a sort again to reverse it.
• Open Favorites, Videos, Screenshots, and Recently Deleted from Collections.
• Hide folders that you do not want to see, for example folders of app icons.

• Swipe between photos. Swipe down to close a photo. Swipe up to see its details and the people in it.
• See the date, the camera data, the file data, and the place where you took the photo.
• See a map of the place, if you turn on Maps.
• Use the film strip at the bottom to move quickly through many photos.
• Zoom into photos and videos.
• See Ultra HDR photos with their full brightness on phones that have a high dynamic range (HDR) screen.
• Play videos at a different speed. Double tap a video to pause it or to skip 10 seconds.
• Start a slideshow.
• Select the text in a photo with the text tools of Android: copy, share, translate, or open a link, a phone number, or an address.
• Turn on subtitles for a video, made on your phone.
• Touch and hold a person or an object to cut it out of the photo. Then copy it, share it, or save it as a new image with a transparent background. When you open a photo of people, a line draws around them to show that you can cut them out.

• See the people in your photos and videos. Lumen puts the photos of each person together.
• Name a person, merge two people, or hide a person.
• Take a photo out of a person with Not This Person.
• Name a face that Lumen did not put with a person, from the details of a photo.
• On the page of a person, show only photos, videos, favorites, or screenshots, and sort them.

• Share, copy, move, rename, rotate, and resize photos.
• Change the date of a photo.
• Set a photo as the wallpaper.
• Let other apps open photos in Lumen. Let other apps get photos from Lumen.
• Bring your favorites from Fossify Gallery or Aves.
• Export your Lumen settings to a file, and import them again.

• Hide photos and folders in Hidden. Lumen uses the same hidden files as Fossify Gallery.
• Lock Hidden with a PIN, a pattern, or a password, and unlock it with your fingerprint or face.
• Encrypt the photos in Hidden, if you turn on Encrypt Hidden.
• Lock all of Lumen with the App Lock.
• Lumen blocks screenshots and screen recordings of Hidden. You can allow them in Settings.

Lumen does its work on your phone. It does not send your photos, their data, or your personal data to a server. Lumen uses the internet for 3 tasks only:

You can turn off Maps and Check Automatically in Settings. Lumen never asks for the location of your phone. It reads only the location that the camera put in each photo.

• An Android phone with Android 11 or later.
• For the smart features, space on the phone for the models. All the models need about 440 MB with the Fast search model, or about 860 MB with the Accurate search model (about 810 MB on a phone with a supported Snapdragon NPU).

The smart features are optional. Lumen works as a gallery without them.

Lumen is available as an APK file, the Android package file, on the Releases page. Lumen is not on F-Droid or Google Play yet.

1. Open the Releases page on your phone.
2. Download the APK file of the latest release.
3. Open the APK file.
4. If Android asks, let your browser install apps.
5. Tap Install.

When a new version is available, Lumen shows it at the top of Settings. To install it, go to Settings, then About, then Software Update.

The smart features use models. A model is a file that lets the phone recognize the contents of a photo. Lumen does not include the models in the app. Lumen downloads them when you ask for them.

After the download, Lumen makes an index of your photos. By default, this work occurs only while your phone charges. Lumen stops the work when the phone gets warm, and starts again later. You can also set a time of night for this work in Scheduled Indexing.

The models are on Hugging Face. Each model has a fixed version. Lumen does a check of each file with its SHA-256 checksum before it uses the file.

Many phones with a Snapdragon processor have an NPU, a part of the processor for AI. On these phones, Lumen runs Smart Search, text detection, and Accurate face recognition on the NPU:

• Indexing photos for Smart Search is about 9 times faster than on the CPU.
• The Accurate search model is a smaller download, about 480 MB instead of 670 MB.
• Accurate face recognition is available only with an NPU. Other phones use Fast.

Lumen supports 40 Snapdragon processors, from the Snapdragon 7 Gen 1 and 8 Gen 1 to the newest ones. The Snapdragon 888 and 888+ are not supported. Before Lumen uses the NPU, it makes sure that the NPU gives the correct results. If it does not, Lumen uses the GPU or the CPU. To see which one Lumen uses, go to Settings, then Smart Search, and look at Runs On.

Cutout runs on the GPU of the phone, because on the phones that we tested, the GPU is faster than the NPU for this model. It needs about 0.2 seconds on a Snapdragon 7 Gen 1.

You need these tools:

• The Java Development Kit (JDK) 17 or later.
• The Android Software Development Kit (SDK) with Android platform 37.
• The Android Native Development Kit (NDK) 30, for the speech engine.

Do these steps:

1. Get the source code. The smart features come from Lumen AI, which Gradle downloads from Maven Central:

   git clone https://github.com/subhashhhhhh/Lumen.git
   cd Lumen

2. Build the debug APK:

   ./gradlew :app:assembleDebug

3. Install the APK on a phone that has USB debugging on:

   adb install app/build/outputs/apk/debug/app-debug.apk

The debug app has a different app ID, com.subhashh.lumen.debug. It does not replace a release version of Lumen.

The release APKs are built and signed by GitHub Actions from the tagged source code of Lumen and Lumen AI, so you can see how each release was made.

The tools folder has scripts for the place names, the icons, and the speed checks. You do not need them to build the app. The scripts that make the model files are in a different repository.

1. Open the Issues page.
2. Do a search for an issue with the same problem.
3. If no issue has the same problem, open a new issue.
4. Write the version of Lumen. You can find it in Settings, then About.
5. Write the name of your phone and the version of Android.
6. Write the steps that cause the problem.

You can also open the Issues page from Lumen. Go to Settings, then About, then Report a Bug.

Lumen is open source under the Apache License 2.0. Copyright 2026 Subhash Gottumukkala.

Lumen uses the work of many open source projects, for example Backdrop by Kyant0, Coil, Telephoto, Media3, ONNX Runtime, LiteRT, and MapLibre. The place names come from GeoNames, and the map data comes from OpenStreetMap. For the full list and the licenses, see NOTICE and Settings, then About, then Open-Source Licenses.