Zebra have a new free 2015 Global Shopper Study (pdf)
that has some useful information if you are creating retail apps.
On the positive side, shoppers are very interested in WiFi and location-based services. This bodes well for the iBeacon related apps I have recently been working on. On the negative side, only 38 percent of respondents trust retailers to protect their personal data. This emphasises that we should explain what we are doing with their data in app store descriptions and in some cases inside the app.
If you are looking for areas in which to innovate, consumers are increasingly seeking customised offers. They are also eager to have email receipts, receive shopping maps, use WiFi hotspots and receive location based assistance.