I'd be surprised people do try to prepare returns on the phone but it does look like Intuit did change the input screen a bit this year to accommodate mobile devices but the feedback from the PTO FB group has not been good.  Personally, I like the input layout from previous years better.

The big selling point with PTO (other than the price point) is that it's in the cloud, so it's mobile (but needing constant internet access is the trade off) and you don't have to worry so much about data backup and security of maintaining a physical drive/server.