You play as Joe (names can be changed), a young man who is down on his luck. Your girlfriend left you for someone with more money, forcing you to move to a dump of an apartment. Your company is closing it's stores as it slowly goes bankrupt, so you'll soon be out of a job. That's when you get a phone call with the news that your father, a biochemist, has been murdered.
In order for you to be able to install this game, you need to enable (allow) installation of applications from unknown sources (Unknown sources) in the phone settings. Usually this item is in the Security section