Is it too much of a drain of resources.
No, its not. Since the backend system (databases, web services, APIs et al) is common for both the website and the app. This is also where most of the maintenance occurs. Besides this, the website and the apps mostly need changes in design but not anything else other than that. Expenses for both is more or less the same. In fact apps could be more expensive since you need to port the app across different platforms which have different architectures while the website is more or less the same across all platforms.
It could be that they are sustaining losses and want to get rid of the website team, which is why they are moving to apps only. That or they want to bring their services closer to the customers than their competitors so that people would prefer to use the app than go on the web, where they risk customers going to their competitors who might offer lesser prices, etc.
In business, everyone cares about profits. No one cares about convenience.
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I also created a thread regarding myntra's app only shopping on the very first day of transformation.
*www.digit.in/forum/chit-chat/191430-install-our-app.html
I was hesitant atfirst but it felt good afterwards and placed two orders.Also there were some in app game which will enable s to score some products for free.I guess we need some more time to evaluate.
Seems like a gimmick to get more customers hooked.
Makkhichoose project 
