it's a decision question.
We are building a vocabulary app. There's a timer and the user should choose the correct synonym of a word before the timer goes off etc. After the timer goes off or the user choses and answer, the correct answer is shown, then the next word. Not much graphics, some cool images only, and a timer etc.
Should we stick only with standard UIViewController methods, or is it better to use Cocos 2d library, or something like that?
Sounds like you really don't need the complexity and weight of Cocos 2d, and could very well do with just NSTimers, UILabels, UIImageViews and UIButtons, and if you need finer control you can use CoreGraphics (it has simple methods for text and images), and system timing APIs (as NSTimer accuracy can be an issue).