4. Angry Birds
Angry Birds is probably the most successful gaming app, with its broad appeal, simple mechanics and addictive formula enticing users of all ages (not to mention its numerous spin offs and ports to consoles). If you really think about it though, are you ever going to complete Angry Birds 100%? Of course not. In order to complete Angry Birds in its entirety, you have to collect three stars on each level, the highest of all honours. While this may sound ridiculously easy, it is possibly one of the most frustrating things of all time (right up there with YouTube adverts and that itch you just can't seem to scratch). Another issue with it, being an app-based game, is that you're not likely to sit on your sofa and play Angry Birds for hours on end. An app is more suited for situations where it's just you and your phone (the train, the doctor's waiting room, the toilet). It would take you an age to fully complete the game. Even without that taken into consideration, the game is notoriously difficult. As the bare minimum, you need to destroy all the pigs to progress to the next level. The score doesn't really factor, unless you're doing it for pride (bravo you). Most gamers are relieved just to complete the level and move on, so there's no need to go back and attempt three stars.