With the Fall 2014 Jive Cloud release (version 8c4), the apps market is disabled by default for new customers. Existing customers will have the apps market enabled but can disable it through the Admin Console. It is no longer necessary (or preferred) to use the apps market for accessing and distributing apps. The preferred method of deploying apps into your community is by uploading the app directly using the add-on mechanism. To distribute your app to a wider audience than just one Jive instance, you can also use the add-ons registry.
If you would like to change the enabled state of the apps market or add-on registry, launch the Admin Console, select the Add-ons tab, choose "Cloud Settings" and adjust the radio button for the desired setting.
For new customers, you may need to contact customer support in order to make this setting viewable.