CampaignSidekick recommends using a laptop or desktop computer, but it is possible to access the desktop site on a mobile device.
You should use Google Chrome or Safari, and after navigating to the campaign URL, (campaign.campaignsidekick.vote) select "Request Desktop Site".
The difficulty in most administrative functions is the size of the screen on a mobile device.
Advanced functions such as creating walklists or checking Block Walker activity will be difficult.
Assigning Walklists and Adding Users are tasks that are fairly easy, but for actions more difficult than those a laptop or desktop.