I have been using the UTS App, a bit of correction from my experience. For PUNE division, there is no option of paperless travel, but paper ticket, meaning you can book your UR/Platform ticket on the app, but you have to collect from a counter or an ATVM, else you will be deemed without ticket. For Mumbai region, paperless as well as paper ticket options are available, you can either book ticket on app, collect it via a counter or ATVM or simply opt for paperless option while booking & go to 'show ticket' option in the app for it to work as an e-ticket to be shown if asked by a checking staff on trains as well as platforms. Thanks!