Cleaning

Mechanism
As a newly introduced feature you can have an unlimited number of friends. This feature allows you to clean the structures on the islands of your friends. This doesn't affect your friends at all, you just gain XP and dollars :)

Why should you do that ? Wow, than i have unlimited income with unlimted number of friends ?
 * You earn for each cleaning the amount of XP according to your level, e.g. as level 24 you receive 24 XP per cleaning.
 * You earn a specific amount of dollars increasing with your level, e.g. as level 24 you receive $2250.

No, because cleaning of structures is limited:
 * You can only clean 3 structures each 24 hours at one specific island.
 * You can only clean up to a maximum amount of structures every 24 hours, e.g. as level 24 you can only clean 51 structures every 24 hours.
 * You can only invite 10 friends in an hour (ver 1.1.9)

Income and Limitations
(numbers in italics are not confirmed yet)

Awards
Sources for the last table: Award