Users of older cellphones near the end of their contract are being targeted by ads steering them to a RadioShack store, a consultant for the company said. The electronics retailer began running ads in November on the Verve Wireless ad network, encouraging consumers with older mobile devices to visit their nearest RadioShack. The campaign takes advantage of Verve\'s dynamic location banner to alert users to the location of the RadioShack nearest them at the time they were seeing the ad, clickz.com reported. By targeting users whose contracts are likely to be expiring, RadioShack is hoping to increase its mobile phone sales. Elizabeth Elliott, senior associate and mobile consultant at Mindshare Chicago, which steered the ad buy for RadioShack, said 40 percent of the company\'s sales comes from mobile devices. \"So we figured if we can communicate to a person on a mobile device knowing that device has been in the market for 18 months or more, we can assume that they may be ready to renew their phones sooner rather than later,\" she said. Targeting older cellphones was possible because Verve\'s network shows \"device type, sometimes model (depending on device) and operating system…all anonymously of course,\" Verve\'s Greg Hallinan said. \"By targeting older BlackBerry devices for example, it is a safe assumption that at a minimum their contract term has passed at least once, and the fact that they are on an older device, OS, etc…you can more accurately infer they are due for an upgrade,\" Hallinan said. The ads appear on sites and in apps on the Verve network that already require the user to provide location data, like those that give weather reports or help find restaurants, clickz.com said. s network shows