See Chatter Recommendations in Salesforce1

In the Salesforce1 mobile browser app, the Chatter feed now includes recommendations to help your users take advantage of useful options. The feed suggests public groups to join and recommends using the Salesforce Today app for event preparation and management.

Group Recommendations

Group recommendations appear in feeds in your internal Salesforce organization and in Salesforce Communities. Chatter suggests public groups that a user hasn’t already joined and staggers recommendations over time to avoid cluttering up feeds. Group recommendations can’t be disabled.

Salesforce Today Recommendation

The Today recommendation appears in your internal organization’s feeds only. Today is an app that helps users plan for and manage their daily meetings, and includes time-saver options like instant access to conference calls, quick logging of events, and more. Today is available in the Salesforce1 downloadable apps only—users who tap the recommendation card are directed to the App Store or Google Play, where they can install the downloadable app and then try out Today.

The Today recommendation is turned on by default and displays twice in users’ feeds, spaced out over a week. If desired, you can disable this recommendation for your organization from Setup. Click Setup | Customize | Chatter | Settings, then deselect the Allow Today Recommendations checkbox. If disabled, all existing Today recommendations are removed from your users’ feeds.