Surprised we are still debating this as both are arguably needed. Your most willing and loyal customers need an app. Everyone else, needs the mobile web.
Is the app dead? It has certainly been written off in conference speeches over the year as well as the occasional alarmist headline, but what we've all pretty much known all along really does now appear to be coming true. Consumers just don't want a mobile phone packed with screen after screen of apps. They don't want to scroll through page after page of icons, looking for an app that only allows them to interact with one brand.
The research also showed that the majority of retailers are focusing on mobile Web marketing. They are putting money into mobile advertising, content and search that will be discovered through a browser, not by swiping right and left a few times before their app logo comes into view. People are accustomed to searching online for relevant content, and the retailers' reaction to apps would suggest they are happy to search on mobile too.