Recs.
Updated
Valiant Hearts: The Great War is a point and click adventure game that costs $4.99 and include sin app purchases that range from $3.99 - $8.99 per item.
Specs
Pros
Pro A game about war where you don't kill anyone
Valiant Hearts tells a story about war, but you're not the one spreading death and misery. Your character simply journeys through battlefields, trenches, and various other locations. You meet other characters and solve puzzles along the way. This is quite refreshing because most modern titles about war always have a gun toting player character.
Pro Simple but satisfying puzzles
The puzzles in Valiant Hearts aren't exactly the most difficult, but they'll often require a little more thought than you initially believe.
One type of the puzzles you'll have to solve is fixing a pipe system. You just have to turn sections of the pipe system until it all fits together.
Even solving something so simple is very satisfying and leaves you with a feeling of achievement.