For solo purposes, will the app get more missions and/or expansions ? i mean i really wanted to enjoy more than that tutorial..

and can i use characters like vader, maul or boba in my team ? i always wonder it

There are two campaigns in the app at the moment:

1. The Flight of the Freedom Fighter is 5 missions. You can get the first "real" mission if you choose to not play the tutorial.

2. Jabba's Realm campaign can be played if you have the Jabba's Realm expansion, and the theme and setting allows you to meet the bounty hunters. It's also very replayable - I played it 4 times, looking forward to playing again with my group.

Maul "just Maul now" however doesn't really work for anyone. You might get him as a random mercenary deployment though.

FFG practically said in the In Flight Report that they will do more app content.

Also, check the Legends of the Alliance forum. It's a better place for LotA questions and discussions.