It's in part a strategy to hide their plans from each other, but it's also to be able to announce their products to the public on their terms and control the timing and pace of the reveal.
You may be able to request trademark application records in those jurisdictions, but I imagine it's more of a process. You would also likely need to know the mark itself or the company filing the mark. In the case of Apple, if they file applications under a shell entity and without knowing the product name, it would be difficult to find the application. Also, given the high number of countries without electronic IP records, there are still plenty of opportunities to hide filings.
That being said, it's likely a loophole that will become increasingly narrow over time as more IP offices go online.
> Surely Apple and Google are primarily worried about revealing their plans to each other and similar companies, not to nascent startups, right?
Generally not. In most cases for a big launch like that the other companies already know about it, either through employee movement or more likely being launch partners in some respect. For example, Google knew about the iPhone launch because they provided the Youtube and Maps apps.
Netflix knew about the iPad and Apple TV for similar reasons (and the Chromecast and FireTV for that matter).
Google supplied the data in former releases of Apple's Maps app, but the app was built and maintained by Apple engineers. The companies did collaborate, but Google did not provide the first-party apps on iPhone 1.0.
Copyright already de facto works that way; you get copyright the moment it is fixed in the relevant medium, there is no publication or public release requirement. Patents have their own complicated things, but part of the definition of a patent is that it is for public release, so "secret patent" is theoretically a contradiction. (As my phrasing suggests I have little long-term confidence in our systems maintaining that truth, but I believe it is true right now.)
There are secret patents in the realm of national defense (think nuclear). The patent doesn't issue until the secrecy order is rescinded and the term begins once issued; IIRC.
It's useful if the startup has something it wants to hide in its trademark application (like a product description that it wants to protect) and can justify the added filing fees. But, there are over 1,000 new US trademark filings every day so in most cases, someone would have to be actively searching for it. Also, often the description that accompanies a trademark application is rather broad, so it may be difficult to determine what the application is for without knowing more. Tech companies like Google and Apple are under much more scrutiny.
IANAL, but it seems like if you have to have secrecy for some reason, it's a solid strategy. But chances are good you'd need a local lawyer in whichever country you want to begin your filing in, and need to pay that lawyer to manage all national correspondence. You'd also have WIPO fees and fees in the US on top of the fees in the origin country. So it's really just cost-benefits.
And surely they can employ people in Tonga and Jamaica to inquire in person about trademark applications, right?
I feel like I must be missing something obvious here.