Get help with painting and weathering 3D models on iPad, importing assets, saving your work and exporting the result. Email [email protected] for help with Decay.
This guide covers Decay 1.1, including features currently in testing. Controls and pack availability can differ between builds. Open About Decay from the PH mark in the header to find your version and build number; include both when you write.
Contact support
Use Decay support in the subject line. Describe what you were trying to do, what happened and what you expected instead. If a project will not open or work appears to be missing, say that first.
- Your Decay version and build number, and whether you installed it from the App Store, TestFlight or a development build.
- Your iPad model and iPadOS version. Include your Apple Pencil model for drawing or gesture problems.
- Steps to reproduce the problem, the exact error message and a screenshot or short recording where useful.
- For import or export problems: format, approximate file size, source application and destination application.
- For pack problems: the pack name and whether the issue is payment, restoration or downloading.
Start with those details. Do not send passwords, verification codes, full payment-card details or confidential client assets. If a sample is needed, use a small file you have permission to share. Diagnostic files can contain file names and device details; review them before sending.
Start a model and find the controls
Open Menu → Files → Open model, or use Start from for a built-in shape. Choose Surface for painting and weathering, Decal for surface images, or Light for painted light and light decals. Lighting, Floor and Texture have separate toolbar controls.
Tap ? for the in-app guide. If the editing panels have disappeared, tap the Clean view window icon again. Clean view hides panels; it does not turn painting off.
The Menu groups actions under Files, Model and App. Earlier builds arrange these differently. If the instructions do not match your screen, send your version and build with a screenshot.
Import a model with its textures
Use an uncompressed GLB with image textures, an FBX with embedded textures, or an OBJ with its MTL file and texture images. Decay also accepts glTF and supported Model I/O mesh formats, including USD/USDZ, STL and PLY. The extension alone does not guarantee support for every feature inside a file.
For linked resources, select the model's folder or select its companion files together. Preserve their relative folder structure. An OBJ alone does not contain the images referenced by its MTL file; glTF may need separate buffers and textures. Make cloud-hosted files available locally in Files before retrying.
If a model opens white, flat or with the wrong material, read the import notes and check that its images were included. Export procedural materials as image textures from the source application. Decay packs multiple materials into one paintable texture set; independent material slots and every shader setting are not retained.
Export a static mesh from Blender first: native .blend projects, animation controls, rigs and custom shaders are not preserved. Draco/meshopt-compressed geometry and KTX2/Basis textures need an uncompressed or conventional-image export. For a failed import, send the error and export settings before sending the model itself.
Finger, Pencil and navigation
Select the hand icon to paint or place decals with one finger. Select the pencil icon to use one finger for rotation and Pencil for editing. Pencil can paint in either mode. Check this setting if touching the model rotates it instead of painting.
- Drag with two fingers to rotate; pinch to zoom.
- Drag with three fingers to pan.
- Use the Undo and Redo toolbar buttons to change edits.
- Use Menu → App → Hand preference to swap the editor layout.
Pencil features depend on the Pencil and iPad. Pressure controls strength and tilt can widen the brush. Pencil Pro squeeze controls require supported hardware; the in-app guide explains those gestures.
If a brush does nothing, check the stage, selected tool and strength, and whether you are viewing the original. Choose Resume editing when an original-preview view is active. Include any active mask or Solo selection in your report.
Place and remove decals
Choose a decal and tap the model to place it. Adjust position, scale, rotation and opacity, then choose Done to apply it. Baking writes the decal into the material maps. Finish or cancel a pending placement before saving.
Use Undo while the edit remains in the current history. Reopening a saved project does not turn baked decals into separately editable layers. The Clean brush restores the underlying original surface and can remove other painted changes in that area too. Save a separate project before making a substantial correction.
Use Your decals → From Photos or From Files for personal images and supported decal packages.
If a personal decal is missing, say how it was imported and whether it disappeared after reopening the app or a project. Keep the original image or package. Removing a library item does not remove a copy already baked onto a model.
Save a project you can edit again
Project saving requires Decay Full. Use Save Project to create a native .decay document. It preserves the model, working material maps, original-surface data, editable weathering and scene settings supported by that build. GLB and OBJ exports are for use in other applications; they do not replace the editable project.
- Finish the stroke and bake or cancel pending placements.
- Choose Save Project. New saves appear under On My iPad → Decay → Projects.
- Use Open Project to reopen a save, or Browse Files for other locations.
- Use Save and Share Project to make a local save and send a copy to a destination you choose.
Undo and Redo history starts fresh after reopening. Save at useful milestones and keep a separate backup of important projects and original assets. Do not rely on automatic recovery of unsaved edits.
If a project needs a newer version, open a copy with a compatible newer build. Renaming its extension does not convert it. If saving fails, keep the current session open where possible, note the error and check available storage before retrying.
Export a model or video
Model export requires Decay Full. Choose Menu → Files → Export GLB for a model with texture maps, or Export OBJ + Textures for an OBJ workflow. Keep the OBJ, material file and texture images together. Open the result in the destination application and check its materials before delivery.
GLB can carry painted emission. The preview's halo and haze are not exported geometry or textures; your renderer may need its own bloom and lighting setup. A reference floor is a preview aid and is excluded from the model export. Imported animation and rig controls do not round-trip through Decay.
In Unity, open GLB files with Unity's glTFast package. It connects every map but does not read Decay's emission strength, so painted light arrives dimmer than it looked in Decay. Raise the material's emission intensity after import.
OBJ keeps each map as a separate image. Many applications connect only the colour map, and some read the height image as a normal map. If the shading looks wrong, connect the _normal, _roughness and _metallic images to the material yourself.
Still images and videos export free with a watermark. Decay Full enables Remove watermark in Cinematic; switch it on before exporting if you want an unmarked file.
Use Cinematic to set up a still image or video and Export MP4 for video output. Wait for completion, then choose a destination in the system share sheet. In builds without a finished-video player, review the MP4 in another app. Seeing the live preview does not mean a video has been saved.
For export problems, include the format, settings, destination app and whether a simple test model has the same issue. Preserve the native project while investigating.
Restore a pack or retry a download
Open Free and paid from the Menu to see Decay Full and optional packs. Use Restore purchases to recover eligible purchases. Use the Apple Account that made the purchase. A website licence key does not restore an Apple in-app purchase. See Apple's purchase-restoration guide for account checks.
ESSENTIALS and LIGHT are included. Each listed expansion includes eight free decals. Full expansions and Decay Full are separate purchases: buying a pack does not unlock saving or model export, and Decay Full does not include the paid packs.
Access and downloading are separate steps. A tile labelled Downloads with pack needs its full-resolution content. Check your connection and storage, then use Try download again if offered. Included samples can remain usable while the rest is unavailable.
Pack availability can differ between App Store, TestFlight and development installations. Apple-hosted packs cannot be downloaded by an ordinary development install. If prices fail to load or a purchase stays pending, send the message and installation type; do not repeatedly purchase to try to fix it.
For a refund on a purchase billed by Apple, follow Apple's refund instructions. For a technical pack problem, email us with its name and an order reference if relevant, removing unrelated receipt details. This does not limit any applicable consumer rights.
Memory warnings, slow performance or crashes
Large meshes, high-resolution textures, layered effects and exports can use substantial memory and storage. New model imports default to 4K. Higher texture settings need more free storage; read the size warning before selecting 8K or 16K. Try a simpler model or smaller texture set to establish whether the problem is specific to one asset. Save a project first if you have Decay Full.
Global Bake commits the finish and clears editing history and live-layer controls. Read its confirmation first. With Decay Full, it saves an editable backup. Without Decay Full, it does not give you a backup you can open, and the bake cannot be undone. It is not an ordinary Save command.
After a crash, reopen Decay and check the last saved project. Unsaved edits may not be recoverable. Do not delete or reinstall the app as a first step: copy out projects and other files you need to keep first. Send the operation that triggered the crash, device and app versions, and whether it repeats on a small model.
Decay 1.1 requires iPadOS 26 or later and checks graphics and memory capability at launch. If an unsupported-device message appears, send its exact text and your iPad model. A supported device is not a guarantee that every model will fit in memory.
Privacy questions
Model and texture editing runs on your iPad. Purchases, pack downloads and optional cloud imports use their respective services. Only send support the files and screenshots needed to explain the problem, with confidential material removed.
For a privacy question, email [email protected].