AppExchange Store is a basic solution, lacks true mobile support
AppExchange Store is a basic solution for hosting a web-based app store with URL links, but lacks true native mobile app support. The promise of "support for all platforms across desktop and mobile including Android, iOS and Windows" is not quite there. The basic "app object" consists of the app name, URL, App type, Categories, Languages, App logo, Tag line, Description and Requirements.
So, although this provides a "display view" for apps, it's not a complete solution. What's missing is an app store infrastructure and life-cycle management (e.g., managing security, workflows, app updates, etc). Here, an "app" is a URL launch point, which means that the SFDC Admin needs to provide everything else behind the scenes.
For example, if you want to support the installation of native iOS or Android app, you would need to create a back-end solution including an XML manifest, installer, and provide separate support for installing, securing, and managing the app. You'd also need to take care of any policies for the app (e.g., app wrapping) or app signing. In addition, if you want to use a "native app store" (i.e., an enterprise app store app for your organization), that would be something you'd need to build separately since AppExchange Store is a website.
The challenge here is that the "PR release" about this SFDC add-on lacks any real detail about the solution, and implies some capabilities that are not really available for mobile users. Note that Salesforce Labs makes the source code available, so enterprising individuals can modify the code to suit their needs.
NOTE: This comment from Cimarron Buser, Apperian. We offer an enterprise-grade mobile application management (MAM) solution. We also use SFDC at Apperian, and I've been a SFDC Admin and user for over 12 years. Always interested in seeing the latest from Salesforce Labs, and they have put out some cool stuff. Also wanted to see how this SFDC add-on might be integrated with Apperian in the future. (This would enable AppExchange features such as role-based views, categories, and analytics, and combine these with the back-end capabilities of a MAM solution.) However, it's not clear yet what the applicability of this would be to enterprises, partners and contractors, since not everyone has a salesforce license.