An Android Image Toolbox Built with Kotlin and Jetpack Compose
You're on your phone, you've got an image that needs work, and you don't want to install five different apps or hand your photos off to some cloud service just to crop, convert, or compress them. Image Toolbox is an Android app that puts a collection of image operations in one place, and it's built entirely with Kotlin and Jetpack Compose.
What It Does
Image Toolbox is an open-source Android application for working with images. It targets API 24 and up, so it runs on a fairly wide range of devices. Under the hood, it's a Kotlin app built on Jetpack Compose, and it follows Material You theming—meaning it should slot into your device's look and feel rather than fighting it.
The repository is a substantial codebase (the README badge clocks it at over 563,000 lines of code, which tells you this isn't a weekend side project). It's actively developed, with a steady stream of commits since the v1.0 tag. The project is distributed through GitHub Releases, and it also appears to have Fastlane metadata set up, which is typical for apps that ship through F-Droid or the Play Store.
The README itself is fairly light on feature-by-feature documentation—it leans on badges and a logo more than prose. So if you're looking for a detailed feature matrix, you won't find it spelled out there. What you will find is a clear signal about the stack and the platform.
Why It's Cool
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It's a Compose-first app you can actually read. Most open-source Android image tools are either ancient View-based codebases or thin wrappers around a library. This one is written in Kotlin with Jetpack Compose, which makes it a useful reference if you're trying to learn how a real, large-scale Compose app is structured. The 563K lines figure suggests there's plenty to dig into.
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Material You support is baked in. The README calls out Material You explicitly. That means dynamic color theming that adapts to the user's wallpaper—a small thing, but it shows the app is being maintained against modern Android conventions rather than coasting on an old design.
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Broad API coverage. Supporting API 24+ means the app isn't chasing only the newest devices. That's a practical decision for an image utility—these are the kinds of apps people expect to work on whatever phone they happen to have.
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It's honest about being a toolbox. The name says it: this is a collection of image operations rather than a single-purpose app. If you've ever wished your photo editor did one more thing without making you pay for a subscription, that framing is appealing.
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The release infrastructure is real. Fastlane metadata, tagged releases, and download badges suggest a project that's set up to ship, not just to demo. That matters if you're considering depending on it or contributing.
One caveat worth being upfront about: the README doesn't list specific tools or transformations. I'm not going to guess at what's inside the toolbox beyond what the badges and description tell us. If you want the feature list, you'll need to look at the app or the source directly.
How to Try It
Getting started is straightforward since this is an app, not a library:
- Head to the releases page and grab the latest APK for your device.
- Sideload it (you'll need to allow installs from unknown sources, since it's not coming through an app store link in the README).
- If you'd rather build it yourself, clone the repo and open it in Android Studio—it's a standard Kotlin/Compose project targeting API 24+.
git clone https://github.com/t8rin/ImageToolbox.git
Once it's running, poke around and see what operations are available. The full repository, including source and release history, lives at github.com/t8rin/ImageToolbox.
Final Thoughts
Image Toolbox is a solid pick if you want a local, open-source image utility on Android—or if you're an Android developer curious about how a large Compose app is put together. The README is thinner than I'd like (a proper feature list would help newcomers), but the signals are good: active commits, modern tooling, and a real release pipeline. It's the kind of project that rewards a quick clone-and-look, whether you're there to use it or to learn from it.
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