An Azure storage account is required for interfacing with Dynamics 365 for Finance and Operations environments. The storage account is used as a temporary storage when uploading attachments from the mobile devices, such as images and pdf files. The storage account is only required if you want to manage large files on the Mobile Client.
If you're going to use attachments that are less than 20 MB in size per file, skip this section. You only need to create an Azure storage account if you expect to use attachments with a file size larger than 20 MB per file on the Mobile Client.
For additional information about Azure Blob storage setup and file size limitations, refer to the "appSettings" table and the text below the table in the article Configure the mobile site. The following app settings must be left blank if you skip the setup in this section:
For DEV and TEST purposes, the General-purpose Azure storage account that is deployed with the Dynamics 365 for Finance and Operations environment can be used. Typically, the storage account can be identified by the resource group associated with the Azure environment.