You can attach a document from your mobile device. Options for the source of your resume will depend on your device and your local storage options. Mobile users should be able to select a resume from a cloud if you have mobile applications such as Microsoft (MS) OneDrive or Apple iCloud on your device.
Other alternatives for adding your work experience:
Submit without a resume document and enter your work experience and other information directly in the application
Save your application as Draft on your mobile device, and then sign on from your desktop to upload a resume located on that platform