I'd like to share my solution for successfully using Google Voice on my Ting phone. For reference, I opted for a new phone number from Ting (i.e., I did not port).
First, configure GVoice as you would for any other phone. GVoice should recognize your handset as a Sprint handset. If you plan on using Google Voice's voicemail as your primary voicemail system, configure that, too. Be aware: the on-screen prompts from Google may provide inaccurate information for initiating call forwarding (on which GVoice relies when activating voicemail for you). See your handset's manual for instructions on properly configuring call forwarding.
This is the most important step: In your Ting Dashboard, load the Settings page for your handset. Uncheck "Call Forwarding can be set on phone." Instead, check "Forward 'No Answer' calls to this number," and type your GVoice number in the corresponding field. This will ensure that GVoice properly "hands off" calls placed to it.
Note that this method has been verified by Ting customer support. Many thanks to Brian for his help and patience.
Using Google Voice on Ting FAQ [Updated November 1, 2013]
Google recently announced sweeping changes to its Google Voice service—changes that could render the contents of this thread inaccurate. See this link (https://plus.google.com/106636280351174936240/posts/MjyncJEbzxK) for additional detail regarding these potential changes, the implementation of which could occur as early as May 2014.
What is Google Voice?
Google Voice (abbreviated "GVoice" or "GV" in this thread) is a service from Google that provides users with a way to "unite" their many telephone numbers. Google Voice users receive a new telephone number and can "link" their existing phone numbers to this new one. When dialed, the new number effectively "rings" all other telephones linked to it. For example, one might link both a home phone and an office phone to a Google Voice number which, when dialed, will cause both the home phone and office phone to ring. Google Voice also offers additional functionality—such as voicemail archiving and transcription, customized voicemail greetings, "do not disturb" protocols, and spam blocking—that users in this thread find useful. For more information, visit http://voice.google.com.
Does Google Voice allow me to make telephone calls over the Internet?
No. Google Voice is not a Voice over Internet Protocol service (or application). Some Ting customers pair Google Voice with GrooveIP to acquire Voice over Internet Protocol functionality.
So why does the Google Voice application ask me to "use Google Voice to make all calls." Isn't it making my telephone calls over the Internet?
No. By making telephone calls "through" Google Voice, you are asking Google Voice to display your Google Voice number as your caller ID information, so that others will see your Google Voice number on their handsets when you call them (and not the caller ID information of, say, the mobile phone or office phone you have linked to Google Voice). You are not making VoIP calls. Using Google Voice to make telephone calls will require you to pay for minutes with Ting. To make VoIP telephone calls, use an application like GrooveIP (see below).
Am I using my Ting minutes when I place calls with Google Voice?
**Yes.** Google Voice is not an application for making free telephone calls.
What does Google Voice cost?
Nothing. Google offers Google Voice for free. Of course, as is the case with any of Google's "free" services, the company uses data collected from Google Voice users to produce and distribute targeted advertising.
I see that Google and Sprint have partnered to allow Sprint customers to deeply integrate Google Voice with their mobile phones. Can I do this?
No. This special integration is available only to Sprint customers, not Ting customers.
Can I send text messages with Google Voice?
Yes. Google Voice features free text messaging to mobile phones in the United States or Canada. By downloading Google's Google Voice application to their Ting handsets, users are able to send and receive text messages without incurring text messaging charges from Ting, drastically reducing their messaging bills. To do this, you must use the Google Voice application and not Android's built-in Messages application. However, Ting users are reporting that sending text messages via the Google Voice application does in fact require a tiny amount of data, though the amount is almost negligible (and using the application over a wifi connection does not incur data charges). Read the thread for these reports.
People are calling my Google Voice number, but my Ting phone isn't ringing. What should I do?
First, be sure your Ting number is properly "linked" to your Google Voice account. You should modify your Google Voice settings to include your Ting telephone number in the list of numbers GV will ring when someone calls your GV number. In your Google Voice dashboard, click "Settings > Phones" to ensure your configurtion is correct. Next, check your Ting dashboard to ensure that the "Call Forwarding can be set on phone" option is unchecked. Instead, check "Forward 'No Answer' calls to this number," and type your GV number in the corresponding field. You should now receive calls placed to your GV number.
What is GrooveIP?
GrooveIP is Android software from snrb Labs that allows users to make telephone calls using their wireless Internet connections rather their cellular connections (something typically called "Voice over Internet Protocol," or "VoIP"). To do this, GrooveIP utilizes Google Voice, so anyone wishing to use GrooveIP must also have a Google Voice account. But using Google Voice does not necessitate the use of GrooveIP. Put another way: While one must use Google Voice in order to to GrooveIP, one needn't use GrooveIP in order to use Google Voice.
So why are you discussing GrooveIP here in a thread about Google Voice?
Many Ting users have found clever ways to use Google Voice and GrooveIP in tandem in order to significantly reduce their monthly Ting bills. Read the thread for more on how this can be done.