How to open projects, use supported features and check precautions.
About this guide
HTML Web Preview: JS CSS JSON lets you view web pages and related files in project folders on iPhone and iPad.
1. Open a project
- Put HTML and its CSS, JavaScript, JSON and image files in one project folder. Keep the original folder structure.
- Download files stored in iCloud Drive to the device through the Files app first.
- Choose Open Folder in the app and select the project folder. If asked for a starting HTML file, choose the file to open.
- Projects open in preview without running JavaScript. Inspect the page and source before running only projects you trust.
- Select JSON or source files from the project file list to read them beside the page. After editing originals in another app, refresh to see the changes.
2. When a page or button does not work
Pages that build their interface with JavaScript may look blank or have unresponsive buttons in preview. Use Trust and Run only after inspecting a project.
Security-restricted execution may limit features such as 3D graphics and audio. Compatibility mode is a separate choice for trusted projects and may allow additional external communication.
3. View JSON and source files
Choose JSON in the project file list to view its formatted contents. The app does not edit original files.
Text previews have a 2 MiB size limit. Larger files may not be available in the text preview.
4. Unsupported features
The app displays existing web files. It does not run Java, Python, PHP or Node.js servers, build React projects, extract ZIP archives or edit source code.
Build projects in their development environment first, then open the output folder.
5. External images and fonts
External HTTPS resource access is a separate setting and is restricted by default. Check whether resources are needed for the project before allowing them.
External-site policies, login requirements and the selected execution mode may prevent resources from loading.
6. Inputs and runtime state
Web execution data is managed in temporary storage. Closing a project, rebuilding its runtime or some transitions to the background can erase inputs and runtime state. Ordinary refreshes may reuse temporary storage. Do not keep important inputs only in temporary runtime state.
Closing or refreshing a project does not clear all execution history. If preparing a new project fails, previous records may be restored. Original project files and the recent-project list are managed separately from temporary runtime state.
7. Display language
You can choose Korean, English, Japanese, Simplified and Traditional Chinese, German, French, Spanish and Brazilian Portuguese. Use Language → Change Language in the app to open Apple Settings and choose a language. External forms and advertising-choice screens may use a different language from the app.
8. Precautions and support
Run only trusted folders and code. Executed projects may access files available in the selected folder or send information outside the device. The app is not a malware scanner or system firewall. Select folders containing only files needed for the project.
Send inquiries and suggestions to avrelo.mail@gmail.com. Include the app version, device and operating-system versions and the steps leading to the problem. Remove personal information from screenshots and do not attach passwords, secret keys or private project originals.