Twitter looks to be building its mobile presence with its latest acquisition. The social network has bought the company behind the alternative Android lockscreen Cover. Cover places the apps you use on the lockscreen based on the time of day and your location. We’re not sure what the implications of this sale are at the moment (trying to compete with Facebook Home, perhaps?). The newly acquired company did not say if they will develop the app further as they integrate into Twitter’s team. In the meantime, the app is still available on Google Play Store.