modify a unity based 3d game

i need that expert who should have experience to maintain the source code in the way that we can get the apk for Play store of android and for app store of iOS. the game is penalty kick soccer game. and i need the right person who can do the following work in that game; 1. Daily Notification: some script change required but already written. 2. UI of Game: Some changes are required. 3. Gameplay: there are already made 4 gameplays of the game. you are needed to add the goalkeeper in those games and also create Online Multiplayer function in the way that a user can play with any of the available online or with his/her facebook friends.