The secret to Etsy's explosive stock growth is something Google and Facebook have been begging app developers to start doing

Tech giants like Google and Facebook have been pushing apps developers to index their apps so they can be trawled by search engines, or linked to, but so far they have faced resistance, Bloomberg reports.

The process is known as "deep linking," and only a few thousand of the millions of apps in existence currently do it.

That might be about to change after the share price explosion Etsy saw on Friday, which was catalyzed by a comment made during Google's earnings call on Thursday. Google said they recently started showing these types of links in search results on iOS, "and developers like Etsy are already seeing a boost in traffic as a result of deep linking."

Etsy's shares surged more than 32% during trading on Friday, rising as high as $22.15 per share, a level not seen since mid-May. Etsy's stock has been down since its April IPO, perhaps due to the development of "Amazon Handmade," an Etsy competitor. But this boost sends a strong signal to app developers about the power of deep linking - especially when Google is pushing it.

Google and Facebook have been frustrated by the lack of progress in deep linking in apps, as it hampers their ability to target users with the most specifically tailored ads, Bloomberg reports. One reason for this sluggishness is time. Deep linking can take up as much as 5% of the time it takes to develop an app, Alex Matjanec of ad agency AD:60 told Bloomberg. But the other reason is simply that these app creators want to hoard certain data for themselves, and not let Google break into their walled kingdoms.

But it's hard to argue with numbers, and Google says the traffic on Etsy's app has increased 12% since they began using Google's indexing.

Facebook product manager says Eddie O'Neil told Bloomberg he believes that developers will continue to adopt deep linking. "It's sort of inevitable, he said." And with today's stock run by Etsy, it might be sooner rather than later.