Colliz - DIY Wallpaper Craft is a mobile app that lands somewhere between a coloring book, a paint-by-numbers project, and a sticker collage maker. You open it up and immediately get a grid of black-and-white line drawings – flowers, animals, geometric patterns, that sort of thing. The basic idea is you tap a section of the drawing, pick a color or pattern from a palette, and fill it in. It feels like one of those adult coloring apps, but the output is meant to be saved as wallpapers for your phone. I found it while browsing the Google Play Store, and it has over a hundred thousand installs with no initial paywall – you can download and launch it for free, though there are in-app purchases and ads once you start playing around. When I first opened the app, the interface felt a bit cluttered, but the concept was clear enough: pick a picture, color it, save it.

After spending some time with it, the app's workflow is straightforward. You scroll through a gallery of templates, pick one that catches your eye, and the painting screen loads. It separates the drawing into numbered or shaded regions, which is handy. You just tap a region, and it highlights all the connected areas of the same number, then you pick your color or pattern. There's a small color palette at the bottom that gives you solid colors, but also some textured fill options like wood grain or brick – which is where the “DIY” part kicks in. The experience was smooth for the most part, but I ran into a moment where I accidentally selected a region that was too tiny to see clearly, and it took a few tries to fix it. A practical tip: zoom in with two fingers before filling small spots, because the touch detection isn't always precise. The onboarding is just a quick tutorial slide, and then you're off. It's not complicated, but I wish it had an undo button that worked more reliably – sometimes it would revert a whole set of actions instead of just the last one.

After using Colliz for a few days, I think it's a decent time-waster if you enjoy digital coloring but want something that feels like you're actually creating a finished product for your phone background. The best part is being able to save the wallpapers directly to your gallery, so it doesn't feel pointless. But it's not a tool for people who want precise control – if you've used something like Procreate or even Adobe Fresco, the coloring here feels more like a game than serious design work. The templates are pretty, but they're locked behind ads or purchases after the first few free ones, which gets annoying quickly. I could see someone who likes casual, relaxing apps like Happy Color or ColoringBook installing this and keeping it, but I personally uninstalled it after a week because the ad frequency and the limited free content just weren't worth it for the novelty.

• 🎨 Colliz lets you fill areas with textured patterns like fabric, wood, or mosaic tiles, which is something you just don't see in most coloring apps like Happy Color. That alone gives your wallpaper a crafted feel instead of looking like a flat digital drawing.
• 🎨 The color palette is not just solid shades – you get gradients and mixed tones that make the final image look more like a real painted texture. Happy Color mostly gives you basic bright colors, so this feels more adult and creative.
• 🎨 The templates are designed specifically for phone screen ratios, so once you finish coloring, the wallpaper fits perfectly without cropping or stretching. In an app like Color by Number, you often have to manually adjust the image to make it work as a background.
• 🎨 There's a pattern library that you can unlock, which lets you apply custom repeating backgrounds inside the image. It's a small touch, but it makes each wallpaper feel unique compared to the standard block-color approach of similar tools.

• 👍 The app has a surprisingly large variety of free templates to start with – while Happy Color gives you maybe a handful before pushing purchases, Colliz offers at least 20-30 that you can color and save without paying a cent.
• 👍 The export quality is solid. When you save a finished wallpaper, it comes out at a good resolution without heavy compression, unlike some free apps that pixelate the output unless you buy the premium version.
• 👍 It supports offline use once the templates are downloaded, so you can color on a commute or in a basement without worrying about mobile data. Not all apps in this space offer that without locking it behind a subscription.

• 👎 Ads appear after almost every few taps, and they're often full-screen video ads that take 5-10 seconds to skip. Compared to something like Color by Number, which has ads but spaces them out better, Colliz feels aggressive and disrupts the flow.
• 👎 The undo feature is unreliable. It would undo a whole group of fills instead of just the last one, which made me restart a couple designs. Happy Color has a cleaner undo system that works step-by-step.
• 👎 The interface is a bit dated and cluttered. The font feels small on a modern screen, and the buttons are packed close together, leading to accidental taps. Apps like ColoringBook have a cleaner, more modern layout that feels easier to navigate.