It is competition from the iPhone (and the possible control of search traffic on mobile devices that Apple would have) that forced Google to focus on Android after acquiring it and this lead to the demise of Nokia and the mobile division of Microsoft.
I don't know if Nokia knew the marketing budget going towards launching the iPhone along with other resources planned for its launch would that have changed their view on how serious of a competitor the iPhone is going to be.
Nokia R&D had a touchscreen-only phone prototype in early noughties. It got killed, and while I have not seen the actual memo, I've heard people quoting from it: "Nokia will never make a touchscreen-only phone."
Apple launched iPhone a few months later.
They tend to be a bit more open when this isn't a concern, for example Apple TV or the new Mac Pro.
Usually it is in neither parties interest to reveal such an event. I know of at least one such instance and the extreme lengths a Chinese competitor went to steal (not google).