????:1???????:???????????

2????????????

3?????app??

4???????

5???????????

????6???21???????  ????????21??????????????????,??????????????,????????????????????,???“??????”????????????

??,???????????,???3.6?????,???????

?????????,????,??????“?????????????????”????,???????????????,??,?????????,?????????,???

????????????????,????????“??”,?“?????”,?????????????????????????????,????,??“??”????????????????????????????????????????“????????????????????”,????????????,????????????????????????,“????”???????“??????????”?

??,?????????????“????????”????,????????????????,??????????,?????“????????????”???????(???????????) ???????????????:?????????????????