[5.1 应用包购买](4.1%E5%BA%94%E7%94%A8%E5%8C%85%E8%B4%AD%E4%B9%B0.md) [5.2 0元商品购买](4.20%E5%85%83%E5%95%86%E5%93%81%E4%B8%8B%E8%BD%BD.md) [5.3 免费商品下载](4.3%E5%85%8D%E8%B4%B9%E5%95%86%E5%93%81%E4%B8%8B%E8%BD%BD.md)