隨著行動裝置與通訊技術的發展，人們可使用智慧型裝置連接到App商店下載各式各樣的App。然而現行App商店的機制，僅可讓App原持有者在多個行動裝置間使用已購買的App，但並未著墨於將App轉移給其他使用者。因此我們提出一套能夠公平且安全轉移App的機制。App開發者可以設定其轉移次數，而且參與轉移的各個角色無法互相欺騙對方而圖利，新持有者也可以決定是否將App再次合法轉移給其他使用者。

By using mobile devices, users can download apps from App Markets. However, App Markets don’t provide transfer-related mechanism. Users are unable to verify the transferred app. In this paper, we propose a count-limit transfer verification mechanism. The mechanism is designed to fairness and transfer app securely. Moreover, App developers can set transfer count to limit the numbers of transfer time. In addition, new owner can validate transfer app by himself. Finally, we build a prototype system to realize the feasibility and practical applicability of proposed mechanism.

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