Can I activate the Mobile App for Inventory Management plugin again?

Can I activate the Mobile App for Inventory Management plugin again?

Yes, you can always choose to reactivate the Mobile App for Inventory Management plugin. However, there are 2 possible scenarios here.
Scenario 1: 
Your reactivation date is BEFORE the end of your current billing cycle. In this case, you just need to click the activate button on the plugin tile (if you are coming from the Plugin screen) OR put a tick on the activation checkbox on the plugin tile (if you are coming from the Manage Account section) to activate it.
Scenario 2: 
Your reactivation date is AFTER the end of your current billing cycle. In this case you will have to again subscribe to the plugin through the normal subscription process.
The Tagrain Handheld mobile application is available on both - Android and iOS and can be downloaded from the respective App stores.