Hitman GO

There are 15 levels in the first chapter. The first 5 serve as a tutorial to ease you in, and only have a single challenge in each. The last 10 are proper full fat levels with the standard 3 challenges per level. The challenges can be done in multiple runs through a level, so they do not have to be done in a single play-through. In fact they often contradict each other, and so HAVE to be done in separate runs. Just keep restarting the level until you clear all 3 before moving on.

Here is a video walkthrough of all the levels in Chapter 1:

For those of you who prefer text guides, see the forum Guide here: LINK