Users of Google Voice have long called for the company to pay more attention to the seemingly forgotten service for quite some time. Unfortunately, they may be getting more than they were hoping for. While many people are thrilled to hear Voice will finally support MMS and become a part of Hangouts in early 2014, Google is also planning to close up shop for all 3rd-party apps that relied on the service for free texting and VoIP calling. Sadly, these apps will cease to function on May 15, 2014.
Google plans to shut down the XMPP interface currently used by alternative Voice apps. XMPP is an open protocol developed and made popular(-ish) by Jabber; its purpose was to allow multiple instant messaging networks to interoperate with each other. Google was an early supporter of the protocol, incorporating it into both its Talk and Voice products. As a part of the transition from Talk to Hangouts, announced at Google I/O in May 2013, XMPP support was cut significantly so that alternative clients can still connect and send messages, but many of the interesting features like video chat and group messaging were made exclusive to Hangouts. Third-party Voice clients won't have it so lucky, as the entire interface will be shut down entirely, and no replacement has been announced. For the sake of anybody using an IM client that interacts with multiple networks (Trillian, Adium, Pidgin, etc.), let's hope this is the last time we have to talk about a shutdown like this.
Among the casualties of this change is GrooVe IP, developed by snrb Labs. In a statement made on the app's Facebook page, development efforts are ending with version 1.4.6, posted just yesterday. GrooVe IP will continue to operate normally until Google locks down Voice in May; snrb Labs intends to issue bug fixes if any critical issues arise between now and then.
Longtime Voice users have probably expected a tightening of the reigns for some time. When apps began to pop up with the ability to make free calls through Google's network, there were already questions about the Terms of Service and if such apps would be permitted. At the time, Google remained mostly silent and its inaction was seen as permission. It was understood that undocumented interfaces could change or go away at any time, but the lack of updates to Google Voice over the years meant that breaking changes rarely occurred, if ever. As Google asserts its commitment to bring all of its messaging systems under the same roof with Hangouts, it was time for Voice's aging interface to be completely overhauled. Naturally, violations to the Terms of Service and a need to secure the network are given as reasons.
If you're a regular user of any 3rd-party app relying on the Google Voice service, you may need to start investigating alternatives. Features like texting and voicemail will obviously transition completely to the Hangouts app, so you won't need to worry about those. The future of free VoIP calling is considerably less certain, and Google hasn't made a statement about plans to introduce such a feature, but we can hope. In the meantime, there are still over seven months to work out plans, so you've got some time.