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 corresponding list, slide the required item to the right and tap Stop or Start.
How can I unarchive a campaign?
In the campaign list, swipe the campaign to the right. Tap Unarchive.
After you unarchive the campaign, it is marked "stopped"; you have to tap Launch if you want the campaign to run again. Additionally, the campaign may automatically be sent for re-moderation. In this case, the ads will not be served until they pass moderation.