Rapid communication: mapping of the titin (TTN) gene to pig chromosome 15.

Embodiments allocate and synchronize virtual currency balance of a user among multiple user devices. A user profile is maintained at a central server. The user profile stores a total virtual currency balance and a designation of multiple user devices associated with the user. The total virtual currency balance may be divided among and allocated to the multiple user devices, for example, based on usage data associated with each user device. The portion of the total virtual currency balance allocated to each user device may be stored locally at a local wallet of the corresponding user device. The local virtual currency balance on a user device may be used to purchase goods or services, such as playing a game. If the locally stored virtual currency balance of a given user device runs low, the user device may request additional virtual currency from other user devices without contacting the central server.