Need to share a document quickly? There are so many apps for that, from Dropbox to OneDrive. And of course there's email, AirPlay, and even the good old USB thumb drive. Now, WhatsApp is joining the document sharing fray.

Some users of the 7-year-old, Facebook-owned messaging service are reporting the appearance of a document-sharing feature when they update to the latest version of the app. TechCrunch has a walkthrough of how it works on iOS; it's also available on Android, but not Windows Phone.

Only PDFs are currently supported, but as Adobe Reader's monopoly on PDF creation crumbles, PDFs cover pretty much any document you'd want to send, from boarding passes to exported Google docs.

WhatsApp passed the one billion user mark as of Feb. 1. It's also undergone some fairly sizeable shifts to its product and business model in recent weeks, as it seeks to capture even more of the mobile messaging market. Perhaps the biggest change is the fact that users no longer have to pay a $1 yearly fee, which was abolished in January.

It faces some competition from Google, which recently launched an effort to improve traditional text messaging, and Yahoo, which is beefing up its Messenger service. It's also been roped in to the recent encryption debate, with a Facebook executive arrested in Brazil for refusing to comply with a judge's request to hand over encrypted WhatsApp messages in a drug-trafficking investigation.

Still, WhatsApp is confident in its future growth. So confident, in fact, that it can afford to end support for legacy devices by the end of 2016, including all BlackBerry phones.

PC Magazine