You can use this app to start and stop impressions and to unarchive campaigns.
How do I start and stop impressions?
You can start and stop campaigns, ad groups, ads and keywords. In the appropriate list, swipe the item to the left and tap Actions. In the list, select Stop or Launch.
How can I unarchive a campaign?
In the campaign list, swipe the campaign to the left. Tap.
After you unarchive a campaign, it is marked as stopped, and to launch it you have to tap. Additionally, the campaign may automatically be sent for re-moderation. In this case, the ads will not be served until they pass moderation.