By Rob Pegoraro

Special for USA TODAY

Q: The Google Voice calling apps you suggested last year will stop working on May 15. Now what?

A: The advice I shared in a column last February will no longer apply because Google is cutting off a way other products could connect to its call-routing service.

Programs like the GrooVe IP and Talkatone apps I'd endorsed last year will get disconnected when Google's support for that "Extensible Messaging and Presence Protocol" connection ends Thursday.

Google has been moving to fold Google Voice into its Hangouts service. But with days to go before this cutoff, the work remains frustratingly unfinished.

• If you're logged into your Google+ account in a Web browser, you can place and take calls on your Google Voice number, although it can take so long for this Web app to connect an incoming call the caller can get dumped to voice mail first.

• If you install the Hangouts app for iOS, you can receive and place calls over Wi-Fi or a data connection, much as you can with non-Google software today.

• But the Hangouts app for Android still can't place calls over the Internet. You need a regular cellular connection, which makes this costly or impossible if you're traveling overseas or only have a Wi-Fi connection.

Most third-party apps and devices being severed from Google Voice suggest users switch to different calling services. Talkatone has already switched to its own "VoIP" system, and Obihai posted a list of a dozen potential replacements last October for its Obi adapters, which let you turn a plain old phone into an Internet phone.

If you want to keep your Google Voice number, you'll have to port it to whatever new service you're using. Google charges $3 for that, and most of these alternatives either cost money or put a cap on the free calls you can make.

If you don't care for your Google Voice number, you could switch to cheaper Internet-calling options like Microsoft's Skype, which allows nearly free calls to any phone number, or Facebook's Messenger, which provides free calls to Facebook friends. I'd suggest Apple's FaceTime, but that only works for calling other iOS devices.

(Disclosure: My work number is on Google Voice, so ditching those digits won't work for me.)

Google could improve this situation by finally adding outbound calling to the Hangouts app for its own operating system. But it also (still!) needs to improve how it conveys these changes to its users.

The news of Google's impending lockout of third-party apps came in a Google+ post from product manager Nikhyl Singhal, as have subsequent updates about the Hangouts app. Memo to Google: Normal people don't have the time to find and follow individual engineers to know what's happening to the apps and services they use.

Asked for comment about possible updates to the Android Hangouts app, a Google representative replied: "We do not have anything to announce at this time."

TIP: ATTACHMENTS IN GMAIL AND OUTLOOK.COM

If you get an e-mail with an attached file — PDF, Word, Excel, PowerPoint and so on — Gmail will display a thumbnail image of it with two buttons: one to download it, another to save it to your Google Drive online storage. But if you click anywhere else in the thumbnail, you'll have a view of the document fill your browser window.

This preview option, like the Quick Look feature I love in OS X, is all you need for the many times when you don't have to edit an attachment. If, however, you need to revise one of those Office files, Microsoft's Outlook.com bests Gmail; click the "View Online" link and it will open in Microsoft's Office Web Apps. On that page, click "Edit in Browser" to start rewriting.

Rob Pegoraro is a tech writer based out of Washington, D.C. To submit a tech question, e-mail Rob at rob@robpegoraro.com. Follow him on Twitter at twitter.com/robpegoraro.