Research: Discoveries from researching existing products on the market

My next task was to research existing products on the market, in order to recognise common conventions in apps. Whilst testing out these apps, coupling my knowledge of other games on the market, I noticed a trend in most games I played.
All apps had 'Objectives' and 'Obstacles'. For instance:

Objectives included:
- Hit/kill something (contact) e.g. "Angry Birds", "Space Invaders"

- Last as long as possible e.g. "Snake", "Helicopter", "Pong"

- Reach a destination e.g. "Vector Runner", "Line Rider", "Frogged"

- Capture an object e.g. "Capture the flag", "Castle Wars"

- Create something e.g. "Tamagotchi", "Farmville"

- Become superior e.g. "Snowball", "Snake"

Obstacles included:
- Avoiding edges/keeping within boundaries e.g. "Helicopter"

- Objects that could hinder your progression into the game (enemies) e.g. "Pacman"

- Objects that could stop you from functioning properly e.g. "Mariokart" (special moves)

These factors I recognised whilst playing various games have been noted and I will be referring back to these notes when creating a concept for an app, as these notes suggest common objectives and obstacles that appear frequently within games.