When to state limits?

Upfront, and again right after selection.

Mobile File Upload

⚙️ Engineering & Technology By CampusDown Wiki Editorial Team Last updated October 27, 2026

Mobile file upload is the process of choosing photos, videos or documents on a device and sending them to an app or website.

Contents

1. Easy selection
2. Progress and failure
3. Errors and security
4. FAQ
5. References

Easy selection

Offer gallery, camera and files. Use accept (MDN, n.d.-a), capture (MDN, n.d.-b), and the photo picker (Android Developers, n.d.). Show 'JPG/PDF, max 10 MB' upfront — core mobile form usability.

Progress and failure

Progress makes waits tolerable (Myers, 1985); per-file progress indicators and bar design help (Harrison et al., 2010). Support resume and retry, and compress first.

Errors and security

Use inline validation with specific messages (W3C, 2023, 3.3.1). Re-check type, content and size on the server and rename files (OWASP Foundation, n.d.). Mention EXIF location.

FAQ

When to state limits?: Upfront, and again right after selection.
Is browser checking enough?: No, validate on the server.

Sources reviewed: 2026-10-27

References

MDN Web Docs. (n.d.-a). <input type="file">. accept and multiple attributes.
MDN Web Docs. (n.d.-b). HTML attribute: capture. Opening the camera directly.
OWASP Foundation. (n.d.). File upload cheat sheet. Server-side upload security.
Android Developers. (n.d.). Photo picker. Permissionless media picking.
Myers, B. A. (1985). The importance of percent-done progress indicators for computer-human interfaces. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (pp. 11–17). ACM. Percent-done indicators.
Harrison, C., Yeo, Z., & Hudson, S. E. (2010). Faster progress bars: Manipulating perceived duration with visual augmentations. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (pp. 1545–1548). ACM. Perceived duration of bars.
World Wide Web Consortium. (2023). Web Content Accessibility Guidelines (WCAG) 2.2. Criterion 3.3.1 error identification.

Reports and materials that use this theory (Korean)

There are no materials dedicated to this theory yet, but you can search related reports in the CampusDown library (Korean).

Find more reports · Search '파일 업로드' on CampusDown →

Progress IndicatorsProgress indicators are spinners, bars and step indicators that show work is under way. Covers response-time research, choosing types by wait length, percent-done effects, designs that shorten perceived time and common mistakes.⚙️ Engineering & Technology Mobile Form UsabilityPrinciples of mobile form usability for sign-up, checkout and contact forms: field count and label placement, input types and autofill, research on error-message timing, accessibility criteria and the link to conversion.⚙️ Engineering & Technology Inline Form ValidationInline validation reports errors or success beside each field before submission. Covers research on its benefits, timing, success indicators, good error copy and accessibility beyond colour alone.⚙️ Engineering & Technology AI Search Algorithms: A* and MinimaxAI search algorithms explained: state-space search, breadth-first and depth-first search, Dijkstra, heuristics and A* (admissibility, consistency), game trees, minimax and alpha-beta pruning, based on the original papers.⚙️ Engineering & Technology

Latest ArticlesView all ›

New guides for college study and assignments (Korean)

This article was last updated on October 27, 2026. It is based on widely recognized original works and textbooks; when citing it in a paper, please check the original sources listed in the references.