Hi,
My name is Rost, I'm from Kharkiv, UKraine.
The list of tasks is quite good, but I may estimate much precisely only with sources in my hands (for mobiles and Ubuntu.
Initially I see a possibility to give you a small fix in the first day, starting from a small milestone to get you understanding about my competence. Complete list with server+mobile modifications in 2-3 days.
Let's start from the crash and move to other fixes. The initial crash would cost $25.
Regards,
Rost