Will the release of a product increase stock price?

I don't understand how stock works

If I buy apple stock right now, will it increase in september because they announce a new iPhone? Or if I buy sony stock, will it increase because they release the ps4?

I'd like to think so, but that would be too easy

Sometimes. Microsoft's new tablet has been a sales flop.

As far as sony go's you needed to buy around the announcement time when they got that great reception. Microsofts stock dropped because of it, hence the reason they decided to scrap half their plans. When it comes to a new version of existing tech like the i phone. Its usually sales based. The more money they make the larger the company grows. What your thinking of is new tech that has some kind of inovation that gives it a Unique selling point.

If they are the only ones doing it and it takes off. Then that will significantly increase their share price.
With that said it could be worth taking a punt, just use a volume indicator to keep an eye on any increase to see if its got legs.