What should I specifically test at cloud storage based mobile applications?

I am developing a sensor based mobile application for iOS and Android. The data produced by smart phone sensors will be stored in the cloud. At this point, I am wondering that what I should test about the data transfer and storing. I mean that for example, I should test the scenario as if the connection corrupts while GPS data transfer not finished. I am not looking for the techniques, or testing styles. I am trying to find possible failure points or test scenarios. I hope that I could explain my point.

Below are some of the things worth considering for your app:

• Incomplete transfers when connection corrupts (as u mentioned)
• Cloud-server size..how much request can it handle at a single instance?
• If u are considering cloud solutions, you should also consider the location of your users from where they will be accessing your app. Users and the location of data center will also affect in the response time.
• Format of the date to stored. Considering a file size which is fast in i/o will also help optimize the speed of the app.
• Asynchronous/Synchronous data transfer
• Security measures on the cloud..may be using services like VPC if you are considering AWS

These are some things worth considering. Thanks :)