So far, I have already viewed Easy Tables, but seems that its focus is on save user data on the cloud, and I don't want to do that.
Easy Tables work with Node.js backend, you just need to add the table and your backend would be automatically created for you. By using Offline Data Sync, you could create and modify data in your local store (e.g. sqlite) when your app is offline mode, then when your app is online you could push local changes to your server or pull changes from your server into your local store. This may be an approach for you and you could just pull the data from server and only read data from your local store.
I have a Xamarin Forms application, and I have to get initial remote data (with images, maybe in urls) and save that data as a cache on my app.
I didn't find a scenario with Easy Tables that the app administrator loads the initial data (maybe by REST calls) and then the app only consumes that data without modifying it.
Per my understanding, if your initial data is more about images, settings and without any sensitive data, I assumed that you could just leverage Azure Blob storage for storing data (image urls or settings within *.json file) or Azure Table storage, and you could leverage the related client SDK to retrieve the data and store into your local sqlite db or files.
I would prefer to use the blob storage and you could control access (Anonymous access or delegated access permissions) to your blob data. For more details, you could refer to Managing security for blobs.
